Merge pull request #2090 from v923z/master

Notebook, Alt-enter : execute cell, append codecell below.

IPython/frontend/html/notebook/static/js/notebook.js

@@ -1,1287 +1,1295 b''
 //----------------------------------------------------------------------------
 //  Copyright (C) 2008-2011  The IPython Development Team
 //
 //  Distributed under the terms of the BSD License.  The full license is in
 //  the file COPYING, distributed as part of this software.
 //----------------------------------------------------------------------------
 
 //============================================================================
 // Notebook
 //============================================================================
 
 var IPython = (function (IPython) {
 
     var utils = IPython.utils;
     var key   = IPython.utils.keycodes;
 
     var Notebook = function (selector) {
         this.read_only = IPython.read_only;
         this.element = $(selector);
         this.element.scroll();
         this.element.data("notebook", this);
         this.next_prompt_number = 1;
         this.kernel = null;
         this.clipboard = null;
         this.paste_enabled = false;
         this.dirty = false;
         this.metadata = {};
         // single worksheet for now
         this.worksheet_metadata = {};
         this.control_key_active = false;
         this.notebook_id = null;
         this.notebook_name = null;
         this.notebook_name_blacklist_re = /[\/\\:]/;
         this.nbformat = 3 // Increment this when changing the nbformat
         this.nbformat_minor = 0 // Increment this when changing the nbformat
         this.style();
         this.create_elements();
         this.bind_events();
     };
 
 
     Notebook.prototype.style = function () {
         $('div#notebook').addClass('border-box-sizing');
     };
 
 
     Notebook.prototype.create_elements = function () {
         // We add this end_space div to the end of the notebook div to:
         // i) provide a margin between the last cell and the end of the notebook
         // ii) to prevent the div from scrolling up when the last cell is being
         // edited, but is too low on the page, which browsers will do automatically.
         var that = this;
         var end_space = $('<div/>').addClass('end_space').height("30%");
         end_space.dblclick(function (e) {
             if (that.read_only) return;
             var ncells = that.ncells();
             that.insert_cell_below('code',ncells-1);
         });
         this.element.append(end_space);
         $('div#notebook').addClass('border-box-sizing');
     };
 
 
     Notebook.prototype.bind_events = function () {
         var that = this;
 
         $([IPython.events]).on('set_next_input.Notebook', function (event, data) {
             var index = that.find_cell_index(data.cell);
             var new_cell = that.insert_cell_below('code',index);
             new_cell.set_text(data.text);
             that.dirty = true;
         });
 
         $([IPython.events]).on('set_dirty.Notebook', function (event, data) {
             that.dirty = data.value;
         });
 
         $([IPython.events]).on('select.Cell', function (event, data) {
             var index = that.find_cell_index(data.cell);
             that.select(index);
         });
 
 
         $(document).keydown(function (event) {
             // console.log(event);
             if (that.read_only) return true;
             
             // Save (CTRL+S) or (AppleKey+S) 
             //metaKey = applekey on mac
             if ((event.ctrlKey || event.metaKey) && event.keyCode==83) { 
                 that.save_notebook();
                 event.preventDefault();
                 return false;
             } else if (event.which === key.ESC) {
                 // Intercept escape at highest level to avoid closing 
                 // websocket connection with firefox
                 event.preventDefault();
             } else if (event.which === key.SHIFT) {
                 // ignore shift keydown
                 return true;
             }
             if (event.which === key.UPARROW && !event.shiftKey) {
                 var cell = that.get_selected_cell();
                 if (cell.at_top()) {
                     event.preventDefault();
                     that.select_prev();
                 };
             } else if (event.which === key.DOWNARROW && !event.shiftKey) {
                 var cell = that.get_selected_cell();
                 if (cell.at_bottom()) {
                     event.preventDefault();
                     that.select_next();
                 };
             } else if (event.which === key.ENTER && event.shiftKey) {
                 that.execute_selected_cell();
                 return false;
+            } else if (event.which === key.ENTER && event.altKey) {
+                // Execute code cell, and insert new in place
+                that.execute_selected_cell();
+                 // Only insert a new cell, if we ended up in an already populated cell
+                if (/\S/.test(that.get_selected_cell().get_text()) == true) {
+                    that.insert_cell_above('code');
+                }
+                return false;
             } else if (event.which === key.ENTER && event.ctrlKey) {
                 that.execute_selected_cell({terminal:true});
                 return false;
             } else if (event.which === 77 && event.ctrlKey && that.control_key_active == false) {
                 that.control_key_active = true;
                 return false;
             } else if (event.which === 88 && that.control_key_active) {
                 // Cut selected cell = x
                 that.cut_cell();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 67 && that.control_key_active) {
                 // Copy selected cell = c
                 that.copy_cell();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 86 && that.control_key_active) {
                 // Paste selected cell = v
                 that.paste_cell();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 68 && that.control_key_active) {
                 // Delete selected cell = d
                 that.delete_cell();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 65 && that.control_key_active) {
                 // Insert code cell above selected = a
                 that.insert_cell_above('code');
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 66 && that.control_key_active) {
                 // Insert code cell below selected = b
                 that.insert_cell_below('code');
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 89 && that.control_key_active) {
                 // To code = y
                 that.to_code();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 77 && that.control_key_active) {
                 // To markdown = m
                 that.to_markdown();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 84 && that.control_key_active) {
                 // To Raw = t
                 that.to_raw();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 49 && that.control_key_active) {
                 // To Heading 1 = 1
                 that.to_heading(undefined, 1);
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 50 && that.control_key_active) {
                 // To Heading 2 = 2
                 that.to_heading(undefined, 2);
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 51 && that.control_key_active) {
                 // To Heading 3 = 3
                 that.to_heading(undefined, 3);
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 52 && that.control_key_active) {
                 // To Heading 4 = 4
                 that.to_heading(undefined, 4);
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 53 && that.control_key_active) {
                 // To Heading 5 = 5
                 that.to_heading(undefined, 5);
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 54 && that.control_key_active) {
                 // To Heading 6 = 6
                 that.to_heading(undefined, 6);
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 79 && that.control_key_active) {
                 // Toggle output = o
                 if (event.shiftKey){
                     that.toggle_output_scroll();
                 } else {
                     that.toggle_output();
                 }
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 83 && that.control_key_active) {
                 // Save notebook = s
                 that.save_notebook();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 74 && that.control_key_active) {
                 // Move cell down = j
                 that.move_cell_down();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 75 && that.control_key_active) {
                 // Move cell up = k
                 that.move_cell_up();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 80 && that.control_key_active) {
                 // Select previous = p
                 that.select_prev();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 78 && that.control_key_active) {
                 // Select next = n
                 that.select_next();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 76 && that.control_key_active) {
                 // Toggle line numbers = l
                 that.cell_toggle_line_numbers();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 73 && that.control_key_active) {
                 // Interrupt kernel = i
                 that.kernel.interrupt();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 190 && that.control_key_active) {
                 // Restart kernel = .  # matches qt console
                 that.restart_kernel();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 72 && that.control_key_active) {
                 // Show keyboard shortcuts = h
                 IPython.quick_help.show_keyboard_shortcuts();
                 that.control_key_active = false;
                 return false;
             } else if (that.control_key_active) {
                 that.control_key_active = false;
                 return true;
             };
             return true;
         });
 
         var collapse_time = function(time){
             var app_height = $('div#main_app').height(); // content height
             var splitter_height = $('div#pager_splitter').outerHeight(true);
             var new_height = app_height - splitter_height;
             that.element.animate({height : new_height + 'px'}, time);
         }
 
         this.element.bind('collapse_pager', function (event,extrap) {
             time = (extrap != undefined) ? ((extrap.duration != undefined ) ? extrap.duration : 'fast') : 'fast';
             collapse_time(time);
         });
 
         var expand_time = function(time) {
             var app_height = $('div#main_app').height(); // content height
             var splitter_height = $('div#pager_splitter').outerHeight(true);
             var pager_height = $('div#pager').outerHeight(true);
             var new_height = app_height - pager_height - splitter_height; 
             that.element.animate({height : new_height + 'px'}, time);
         }
 
         this.element.bind('expand_pager', function (event, extrap) {
             time = (extrap != undefined) ? ((extrap.duration != undefined ) ? extrap.duration : 'fast') : 'fast';
             expand_time(time);
         });
 
         $(window).bind('beforeunload', function () {
             // TODO: Make killing the kernel configurable.
             var kill_kernel = false;
             if (kill_kernel) {
                 that.kernel.kill();
             }
             if (that.dirty && ! that.read_only) {
                 return "You have unsaved changes that will be lost if you leave this page.";
             };
             // Null is the *only* return value that will make the browser not
             // pop up the "don't leave" dialog.
             return null;
         });
     };
 
 
     Notebook.prototype.scroll_to_bottom = function () {
         this.element.animate({scrollTop:this.element.get(0).scrollHeight}, 0);
     };
 
 
     Notebook.prototype.scroll_to_top = function () {
         this.element.animate({scrollTop:0}, 0);
     };
 
 
     // Cell indexing, retrieval, etc.
 
     Notebook.prototype.get_cell_elements = function () {
         return this.element.children("div.cell");
     };
 
 
     Notebook.prototype.get_cell_element = function (index) {
         var result = null;
         var e = this.get_cell_elements().eq(index);
         if (e.length !== 0) {
             result = e;
         }
         return result;
     };
 
 
     Notebook.prototype.ncells = function (cell) {
         return this.get_cell_elements().length;
     };
 
 
     // TODO: we are often calling cells as cells()[i], which we should optimize
     // to cells(i) or a new method.
     Notebook.prototype.get_cells = function () {
         return this.get_cell_elements().toArray().map(function (e) {
             return $(e).data("cell");
         });
     };
 
 
     Notebook.prototype.get_cell = function (index) {
         var result = null;
         var ce = this.get_cell_element(index);
         if (ce !== null) {
             result = ce.data('cell');
         }
         return result;
     }
 
 
     Notebook.prototype.get_next_cell = function (cell) {
         var result = null;
         var index = this.find_cell_index(cell);
         if (index !== null && index < this.ncells()) {
             result = this.get_cell(index+1);
         }
         return result;
     }
 
 
     Notebook.prototype.get_prev_cell = function (cell) {
         var result = null;
         var index = this.find_cell_index(cell);
         if (index !== null && index > 1) {
             result = this.get_cell(index-1);
         }
         return result;
     }
 
     Notebook.prototype.find_cell_index = function (cell) {
         var result = null;
         this.get_cell_elements().filter(function (index) {
             if ($(this).data("cell") === cell) {
                 result = index;
             };
         });
         return result;
     };
 
 
     Notebook.prototype.index_or_selected = function (index) {
         var i;
         if (index === undefined || index === null) {
             i = this.get_selected_index();
             if (i === null) {
                 i = 0;
             }
         } else {
             i = index;
         }
         return i;
     };
 
 
     Notebook.prototype.get_selected_cell = function () {
         var index = this.get_selected_index();
         return this.get_cell(index);
     };
 
 
     Notebook.prototype.is_valid_cell_index = function (index) {
         if (index !== null && index >= 0 && index < this.ncells()) {
             return true;
         } else {
             return false;
         };
     }
 
     Notebook.prototype.get_selected_index = function () {
         var result = null;
         this.get_cell_elements().filter(function (index) {
             if ($(this).data("cell").selected === true) {
                 result = index;
             };
         });
         return result;
     };
 
 
     // Cell selection.
 
     Notebook.prototype.select = function (index) {
         if (index !== undefined && index >= 0 && index < this.ncells()) {
             sindex = this.get_selected_index()
             if (sindex !== null && index !== sindex) {
                 this.get_cell(sindex).unselect();
             };
             var cell = this.get_cell(index)
             cell.select();
             if (cell.cell_type === 'heading') {
                 $([IPython.events]).trigger('selected_cell_type_changed.Notebook',
                     {'cell_type':cell.cell_type,level:cell.level}
                 );
             } else {
                 $([IPython.events]).trigger('selected_cell_type_changed.Notebook',
                     {'cell_type':cell.cell_type}
                 );
             };
         };
         return this;
     };
 
 
     Notebook.prototype.select_next = function () {
         var index = this.get_selected_index();
         if (index !== null && index >= 0 && (index+1) < this.ncells()) {
             this.select(index+1);
         };
         return this;
     };
 
 
     Notebook.prototype.select_prev = function () {
         var index = this.get_selected_index();
         if (index !== null && index >= 0 && (index-1) < this.ncells()) {
             this.select(index-1);
         };
         return this;
     };
 
 
     // Cell movement
 
     Notebook.prototype.move_cell_up = function (index) {
         var i = this.index_or_selected();
         if (i !== null && i < this.ncells() && i > 0) {
             var pivot = this.get_cell_element(i-1);
             var tomove = this.get_cell_element(i);
             if (pivot !== null && tomove !== null) {
                 tomove.detach();
                 pivot.before(tomove);
                 this.select(i-1);
             };
         };
         this.dirty = true;
         return this;
     };
 
 
     Notebook.prototype.move_cell_down = function (index) {
         var i = this.index_or_selected();
         if (i !== null && i < (this.ncells()-1) && i >= 0) {
             var pivot = this.get_cell_element(i+1);
             var tomove = this.get_cell_element(i);
             if (pivot !== null && tomove !== null) {
                 tomove.detach();
                 pivot.after(tomove);
                 this.select(i+1);
             };
         };
         this.dirty = true;
         return this;
     };
 
 
     Notebook.prototype.sort_cells = function () {
         // This is not working right now. Calling this will actually crash
         // the browser. I think there is an infinite loop in here...
         var ncells = this.ncells();
         var sindex = this.get_selected_index();
         var swapped;
         do {
             swapped = false;
             for (var i=1; i<ncells; i++) {
                 current = this.get_cell(i);
                 previous = this.get_cell(i-1);
                 if (previous.input_prompt_number > current.input_prompt_number) {
                     this.move_cell_up(i);
                     swapped = true;
                 };
             };
         } while (swapped);
         this.select(sindex);
         return this;
     };
 
     // Insertion, deletion.
 
     Notebook.prototype.delete_cell = function (index) {
         var i = this.index_or_selected(index);
         if (this.is_valid_cell_index(i)) {
             var ce = this.get_cell_element(i);
             ce.remove();
             if (i === (this.ncells())) {
                 this.select(i-1);
             } else {
                 this.select(i);
             };
             this.dirty = true;
         };
         return this;
     };
 
 
     Notebook.prototype.insert_cell_below = function (type, index) {
         // type = ('code','html','markdown')
         // index = cell index or undefined to insert below selected
         index = this.index_or_selected(index);
         var cell = null;
         if (this.ncells() === 0 || this.is_valid_cell_index(index)) {
             if (type === 'code') {
                 cell = new IPython.CodeCell(this.kernel);
                 cell.set_input_prompt();
             } else if (type === 'markdown') {
                 cell = new IPython.MarkdownCell();
             } else if (type === 'html') {
                 cell = new IPython.HTMLCell();
             } else if (type === 'raw') {
                 cell = new IPython.RawCell();
             } else if (type === 'heading') {
                 cell = new IPython.HeadingCell();
             };
             if (cell !== null) {
                 if (this.ncells() === 0) {
                     this.element.find('div.end_space').before(cell.element);
                 } else if (this.is_valid_cell_index(index)) {
                     this.get_cell_element(index).after(cell.element);
                 };
                 cell.render();
                 this.select(this.find_cell_index(cell));
                 this.dirty = true;
                 return cell;
             };
         };
         return cell;
     };
 
 
     Notebook.prototype.insert_cell_above = function (type, index) {
         // type = ('code','html','markdown')
         // index = cell index or undefined to insert above selected
         index = this.index_or_selected(index);
         var cell = null;
         if (this.ncells() === 0 || this.is_valid_cell_index(index)) {
             if (type === 'code') {
                 cell = new IPython.CodeCell(this.kernel);
                 cell.set_input_prompt();
             } else if (type === 'markdown') {
                 cell = new IPython.MarkdownCell();
             } else if (type === 'html') {
                 cell = new IPython.HTMLCell();
             } else if (type === 'raw') {
                 cell = new IPython.RawCell();
             } else if (type === 'heading') {
                 cell = new IPython.HeadingCell();
             };
             if (cell !== null) {
                 if (this.ncells() === 0) {
                     this.element.find('div.end_space').before(cell.element);
                 } else if (this.is_valid_cell_index(index)) {
                     this.get_cell_element(index).before(cell.element);
                 };
                 cell.render();
                 this.select(this.find_cell_index(cell));
                 this.dirty = true;
                 return cell;
             };
         };
         return cell;
     };
 
 
     Notebook.prototype.to_code = function (index) {
         var i = this.index_or_selected(index);
         if (this.is_valid_cell_index(i)) {
             var source_element = this.get_cell_element(i);
             var source_cell = source_element.data("cell");
             if (!(source_cell instanceof IPython.CodeCell)) {
                 target_cell = this.insert_cell_below('code',i);
                 var text = source_cell.get_text();
                 if (text === source_cell.placeholder) {
                     text = '';
                 }
                 target_cell.set_text(text);
                 // make this value the starting point, so that we can only undo
                 // to this state, instead of a blank cell
                 target_cell.code_mirror.clearHistory();
                 source_element.remove();
                 this.dirty = true;
             };
         };
     };
 
 
     Notebook.prototype.to_markdown = function (index) {
         var i = this.index_or_selected(index);
         if (this.is_valid_cell_index(i)) {
             var source_element = this.get_cell_element(i);
             var source_cell = source_element.data("cell");
             if (!(source_cell instanceof IPython.MarkdownCell)) {
                 target_cell = this.insert_cell_below('markdown',i);
                 var text = source_cell.get_text();
                 if (text === source_cell.placeholder) {
                     text = '';
                 };
                 // The edit must come before the set_text.
                 target_cell.edit();
                 target_cell.set_text(text);
                 // make this value the starting point, so that we can only undo
                 // to this state, instead of a blank cell
                 target_cell.code_mirror.clearHistory();
                 source_element.remove();
                 this.dirty = true;
             };
         };
     };
 
 
     Notebook.prototype.to_html = function (index) {
         var i = this.index_or_selected(index);
         if (this.is_valid_cell_index(i)) {
             var source_element = this.get_cell_element(i);
             var source_cell = source_element.data("cell");
             var target_cell = null;
             if (!(source_cell instanceof IPython.HTMLCell)) {
                 target_cell = this.insert_cell_below('html',i);
                 var text = source_cell.get_text();
                 if (text === source_cell.placeholder) {
                     text = '';
                 };
                 // The edit must come before the set_text.
                 target_cell.edit();
                 target_cell.set_text(text);
                 // make this value the starting point, so that we can only undo
                 // to this state, instead of a blank cell
                 target_cell.code_mirror.clearHistory();
                 source_element.remove();
                 this.dirty = true;
             };
         };
     };
 
 
     Notebook.prototype.to_raw = function (index) {
         var i = this.index_or_selected(index);
         if (this.is_valid_cell_index(i)) {
             var source_element = this.get_cell_element(i);
             var source_cell = source_element.data("cell");
             var target_cell = null;
             if (!(source_cell instanceof IPython.RawCell)) {
                 target_cell = this.insert_cell_below('raw',i);
                 var text = source_cell.get_text();
                 if (text === source_cell.placeholder) {
                     text = '';
                 };
                 // The edit must come before the set_text.
                 target_cell.edit();
                 target_cell.set_text(text);
                 // make this value the starting point, so that we can only undo
                 // to this state, instead of a blank cell
                 target_cell.code_mirror.clearHistory();
                 source_element.remove();
                 this.dirty = true;
             };
         };
     };
 
 
     Notebook.prototype.to_heading = function (index, level) {
         level = level || 1;
         var i = this.index_or_selected(index);
         if (this.is_valid_cell_index(i)) {
             var source_element = this.get_cell_element(i);
             var source_cell = source_element.data("cell");
             var target_cell = null;
             if (source_cell instanceof IPython.HeadingCell) {
                 source_cell.set_level(level);
             } else {
                 target_cell = this.insert_cell_below('heading',i);
                 var text = source_cell.get_text();
                 if (text === source_cell.placeholder) {
                     text = '';
                 };
                 // The edit must come before the set_text.
                 target_cell.set_level(level);
                 target_cell.edit();
                 target_cell.set_text(text);
                 // make this value the starting point, so that we can only undo
                 // to this state, instead of a blank cell
                 target_cell.code_mirror.clearHistory();
                 source_element.remove();
                 this.dirty = true;
             };
             $([IPython.events]).trigger('selected_cell_type_changed.Notebook',
                 {'cell_type':'heading',level:level}
             );
         };
     };
 
 
     // Cut/Copy/Paste
 
     Notebook.prototype.enable_paste = function () {
         var that = this;
         if (!this.paste_enabled) {
             $('#paste_cell').removeClass('ui-state-disabled')
                 .on('click', function () {that.paste_cell();});
             $('#paste_cell_above').removeClass('ui-state-disabled')
                 .on('click', function () {that.paste_cell_above();});
             $('#paste_cell_below').removeClass('ui-state-disabled')
                 .on('click', function () {that.paste_cell_below();});
             this.paste_enabled = true;
         };
     };
 
 
     Notebook.prototype.disable_paste = function () {
         if (this.paste_enabled) {
             $('#paste_cell').addClass('ui-state-disabled').off('click');
             $('#paste_cell_above').addClass('ui-state-disabled').off('click');
             $('#paste_cell_below').addClass('ui-state-disabled').off('click');
             this.paste_enabled = false;
         };
     };
 
 
     Notebook.prototype.cut_cell = function () {
         this.copy_cell();
         this.delete_cell();
     }
 
     Notebook.prototype.copy_cell = function () {
         var cell = this.get_selected_cell();
         this.clipboard = cell.toJSON();
         this.enable_paste();
     };
 
 
     Notebook.prototype.paste_cell = function () {
         if (this.clipboard !== null && this.paste_enabled) {
             var cell_data = this.clipboard;
             var new_cell = this.insert_cell_above(cell_data.cell_type);
             new_cell.fromJSON(cell_data);
             old_cell = this.get_next_cell(new_cell);
             this.delete_cell(this.find_cell_index(old_cell));
             this.select(this.find_cell_index(new_cell));
         };
     };
 
 
     Notebook.prototype.paste_cell_above = function () {
         if (this.clipboard !== null && this.paste_enabled) {
             var cell_data = this.clipboard;
             var new_cell = this.insert_cell_above(cell_data.cell_type);
             new_cell.fromJSON(cell_data);
         };
     };
 
 
     Notebook.prototype.paste_cell_below = function () {
         if (this.clipboard !== null && this.paste_enabled) {
             var cell_data = this.clipboard;
             var new_cell = this.insert_cell_below(cell_data.cell_type);
             new_cell.fromJSON(cell_data);
         };
     };
 
 
     // Split/merge
 
     Notebook.prototype.split_cell = function () {
         // Todo: implement spliting for other cell types.
         var cell = this.get_selected_cell();
         if (cell.is_splittable()) {
             texta = cell.get_pre_cursor();
             textb = cell.get_post_cursor();
             if (cell instanceof IPython.CodeCell) {
                 cell.set_text(texta);
                 var new_cell = this.insert_cell_below('code');
                 new_cell.set_text(textb);
             } else if (cell instanceof IPython.MarkdownCell) {
                 cell.set_text(texta);
                 cell.render();
                 var new_cell = this.insert_cell_below('markdown');
                 new_cell.edit(); // editor must be visible to call set_text
                 new_cell.set_text(textb);
                 new_cell.render();
             } else if (cell instanceof IPython.HTMLCell) {
                 cell.set_text(texta);
                 cell.render();
                 var new_cell = this.insert_cell_below('html');
                 new_cell.edit(); // editor must be visible to call set_text
                 new_cell.set_text(textb);
                 new_cell.render();
             };
         };
     };
 
 
     Notebook.prototype.merge_cell_above = function () {
         var index = this.get_selected_index();
         var cell = this.get_cell(index);
         if (index > 0) {
             upper_cell = this.get_cell(index-1);
             upper_text = upper_cell.get_text();
             text = cell.get_text();
             if (cell instanceof IPython.CodeCell) {
                 cell.set_text(upper_text+'\n'+text);
             } else if (cell instanceof IPython.MarkdownCell || cell instanceof IPython.HTMLCell) {
                 cell.edit();
                 cell.set_text(upper_text+'\n'+text);
                 cell.render();
             };
             this.delete_cell(index-1);
             this.select(this.find_cell_index(cell));
         };
     };
 
 
     Notebook.prototype.merge_cell_below = function () {
         var index = this.get_selected_index();
         var cell = this.get_cell(index);
         if (index < this.ncells()-1) {
             lower_cell = this.get_cell(index+1);
             lower_text = lower_cell.get_text();
             text = cell.get_text();
             if (cell instanceof IPython.CodeCell) {
                 cell.set_text(text+'\n'+lower_text);
             } else if (cell instanceof IPython.MarkdownCell || cell instanceof IPython.HTMLCell) {
                 cell.edit();
                 cell.set_text(text+'\n'+lower_text);
                 cell.render();
             };
             this.delete_cell(index+1);
             this.select(this.find_cell_index(cell));
         };
     };
 
 
     // Cell collapsing and output clearing
 
     Notebook.prototype.collapse = function (index) {
         var i = this.index_or_selected(index);
         this.get_cell(i).collapse();
         this.dirty = true;
     };
 
 
     Notebook.prototype.expand = function (index) {
         var i = this.index_or_selected(index);
         this.get_cell(i).expand();
         this.dirty = true;
     };
 
 
     Notebook.prototype.toggle_output = function (index) {
         var i = this.index_or_selected(index);
         this.get_cell(i).toggle_output();
         this.dirty = true;
     };
 
 
     Notebook.prototype.toggle_output_scroll = function (index) {
         var i = this.index_or_selected(index);
         this.get_cell(i).toggle_output_scroll();
     };
 
 
     Notebook.prototype.collapse_all_output = function () {
         var ncells = this.ncells();
         var cells = this.get_cells();
         for (var i=0; i<ncells; i++) {
             if (cells[i] instanceof IPython.CodeCell) {
                 cells[i].output_area.collapse();
             }
         };
         // this should not be set if the `collapse` key is removed from nbformat
         this.dirty = true;
     };
 
 
     Notebook.prototype.scroll_all_output = function () {
         var ncells = this.ncells();
         var cells = this.get_cells();
         for (var i=0; i<ncells; i++) {
             if (cells[i] instanceof IPython.CodeCell) {
                 cells[i].output_area.expand();
                 cells[i].output_area.scroll_if_long(20);
             }
         };
         // this should not be set if the `collapse` key is removed from nbformat
         this.dirty = true;
     };
 
 
     Notebook.prototype.expand_all_output = function () {
         var ncells = this.ncells();
         var cells = this.get_cells();
         for (var i=0; i<ncells; i++) {
             if (cells[i] instanceof IPython.CodeCell) {
                 cells[i].output_area.expand();
                 cells[i].output_area.unscroll_area();
             }
         };
         // this should not be set if the `collapse` key is removed from nbformat
         this.dirty = true;
     };
 
 
     Notebook.prototype.clear_all_output = function () {
         var ncells = this.ncells();
         var cells = this.get_cells();
         for (var i=0; i<ncells; i++) {
             if (cells[i] instanceof IPython.CodeCell) {
                 cells[i].clear_output(true,true,true);
                 // Make all In[] prompts blank, as well
                 // TODO: make this configurable (via checkbox?)
                 cells[i].set_input_prompt();
             }
         };
         this.dirty = true;
     };
 
 
     // Other cell functions: line numbers, ...
 
     Notebook.prototype.cell_toggle_line_numbers = function() {
         this.get_selected_cell().toggle_line_numbers();
     };
 
     // Kernel related things
 
     Notebook.prototype.start_kernel = function () {
         var base_url = $('body').data('baseKernelUrl') + "kernels";
         this.kernel = new IPython.Kernel(base_url);
         this.kernel.start(this.notebook_id);
         // Now that the kernel has been created, tell the CodeCells about it.
         var ncells = this.ncells();
         for (var i=0; i<ncells; i++) {
             var cell = this.get_cell(i);
             if (cell instanceof IPython.CodeCell) {
                 cell.set_kernel(this.kernel)
             };
         };
     };
 
 
     Notebook.prototype.restart_kernel = function () {
         var that = this;
         var dialog = $('<div/>');
         dialog.html('Do you want to restart the current kernel?  You will lose all variables defined in it.');
         $(document).append(dialog);
         dialog.dialog({
             resizable: false,
             modal: true,
             title: "Restart kernel or continue running?",
             closeText: '',
             buttons : {
                 "Restart": function () {
                     that.kernel.restart();
                     $(this).dialog('close');
                 },
                 "Continue running": function () {
                     $(this).dialog('close');
                 }
             }
         });
     };
 
 
     Notebook.prototype.execute_selected_cell = function (options) {
         // add_new: should a new cell be added if we are at the end of the nb
         // terminal: execute in terminal mode, which stays in the current cell
         default_options = {terminal: false, add_new: true};
         $.extend(default_options, options);
         var that = this;
         var cell = that.get_selected_cell();
         var cell_index = that.find_cell_index(cell);
         if (cell instanceof IPython.CodeCell) {
             cell.execute();
         } else if (cell instanceof IPython.HTMLCell) {
             cell.render();
         }
         if (default_options.terminal) {
             cell.select_all();
         } else {
             if ((cell_index === (that.ncells()-1)) && default_options.add_new) {
                 that.insert_cell_below('code');
                 // If we are adding a new cell at the end, scroll down to show it.
                 that.scroll_to_bottom();
             } else {
                 that.select(cell_index+1);
             };
         };
         this.dirty = true;
     };
 
 
     Notebook.prototype.execute_all_cells = function () {
         var ncells = this.ncells();
         for (var i=0; i<ncells; i++) {
             this.select(i);
             this.execute_selected_cell({add_new:false});
         };
         this.scroll_to_bottom();
     };
 
     // Persistance and loading
 
     Notebook.prototype.get_notebook_id = function () {
         return this.notebook_id;
     };
 
 
     Notebook.prototype.get_notebook_name = function () {
         return this.notebook_name;
     };
 
 
     Notebook.prototype.set_notebook_name = function (name) {
         this.notebook_name = name;
     };
 
 
     Notebook.prototype.test_notebook_name = function (nbname) {
         nbname = nbname || '';
         if (this.notebook_name_blacklist_re.test(nbname) == false && nbname.length>0) {
             return true;
         } else {
             return false;
         };
     };
 
 
     Notebook.prototype.fromJSON = function (data) {
         var ncells = this.ncells();
         var i;
         for (i=0; i<ncells; i++) {
             // Always delete cell 0 as they get renumbered as they are deleted.
             this.delete_cell(0);
         };
         // Save the metadata and name.
         this.metadata = data.metadata;
         this.notebook_name = data.metadata.name;
         // Only handle 1 worksheet for now.
         var worksheet = data.worksheets[0];
         if (worksheet !== undefined) {
             if (worksheet.metadata) {
                 this.worksheet_metadata = worksheet.metadata;
             }
             var new_cells = worksheet.cells;
             ncells = new_cells.length;
             var cell_data = null;
             var new_cell = null;
             for (i=0; i<ncells; i++) {
                 cell_data = new_cells[i];
                 // VERSIONHACK: plaintext -> raw
                 // handle never-released plaintext name for raw cells
                 if (cell_data.cell_type === 'plaintext'){
                     cell_data.cell_type = 'raw';
                 }
                 
                 new_cell = this.insert_cell_below(cell_data.cell_type);
                 new_cell.fromJSON(cell_data);
             };
         };
         if (data.worksheets.length > 1) {
             var dialog = $('<div/>');
             dialog.html("This notebook has " + data.worksheets.length + " worksheets, " +
             "but this version of IPython can only handle the first.  " +
             "If you save this notebook, worksheets after the first will be lost."
             );
             this.element.append(dialog);
             dialog.dialog({
                 resizable: false,
                 modal: true,
                 title: "Multiple worksheets",
                 closeText: "",
                 close: function(event, ui) {$(this).dialog('destroy').remove();},
                 buttons : {
                     "OK": function () {
                         $(this).dialog('close');
                     }
                 },
                 width: 400
             });
         }
     };
 
 
     Notebook.prototype.toJSON = function () {
         var cells = this.get_cells();
         var ncells = cells.length;
         var cell_array = new Array(ncells);
         for (var i=0; i<ncells; i++) {
             cell_array[i] = cells[i].toJSON();
         };
         var data = {
             // Only handle 1 worksheet for now.
             worksheets : [{
                 cells: cell_array,
                 metadata: this.worksheet_metadata
             }],
             metadata : this.metadata
         };
         return data;
     };
 
     Notebook.prototype.save_notebook = function () {
         // We may want to move the name/id/nbformat logic inside toJSON?
         var data = this.toJSON();
         data.metadata.name = this.notebook_name;
         data.nbformat = this.nbformat;
         data.nbformat_minor = this.nbformat_minor;
         // We do the call with settings so we can set cache to false.
         var settings = {
             processData : false,
             cache : false,
             type : "PUT",
             data : JSON.stringify(data),
             headers : {'Content-Type': 'application/json'},
             success : $.proxy(this.save_notebook_success,this),
             error : $.proxy(this.save_notebook_error,this)
         };
         $([IPython.events]).trigger('notebook_saving.Notebook');
         var url = $('body').data('baseProjectUrl') + 'notebooks/' + this.notebook_id;
         $.ajax(url, settings);
     };
 
 
     Notebook.prototype.save_notebook_success = function (data, status, xhr) {
         this.dirty = false;
         $([IPython.events]).trigger('notebook_saved.Notebook');
     };
 
 
     Notebook.prototype.save_notebook_error = function (xhr, status, error_msg) {
         $([IPython.events]).trigger('notebook_save_failed.Notebook');
     };
 
 
     Notebook.prototype.load_notebook = function (notebook_id) {
         var that = this;
         this.notebook_id = notebook_id;
         // We do the call with settings so we can set cache to false.
         var settings = {
             processData : false,
             cache : false,
             type : "GET",
             dataType : "json",
             success : $.proxy(this.load_notebook_success,this),
             error : $.proxy(this.load_notebook_error,this),
         };
         $([IPython.events]).trigger('notebook_loading.Notebook');
         var url = $('body').data('baseProjectUrl') + 'notebooks/' + this.notebook_id;
         $.ajax(url, settings);
     };
 
 
     Notebook.prototype.load_notebook_success = function (data, status, xhr) {
         this.fromJSON(data);
         if (this.ncells() === 0) {
             this.insert_cell_below('code');
         };
         this.dirty = false;
         this.select(0);
         this.scroll_to_top();
         if (data.orig_nbformat !== undefined && data.nbformat !== data.orig_nbformat) {
             msg = "This notebook has been converted from an older " +
             "notebook format (v"+data.orig_nbformat+") to the current notebook " +
             "format (v"+data.nbformat+"). The next time you save this notebook, the " +
             "newer notebook format will be used and older verions of IPython " +
             "may not be able to read it. To keep the older version, close the " +
             "notebook without saving it.";
             var dialog = $('<div/>');
             dialog.html(msg);
             this.element.append(dialog);
             dialog.dialog({
                 resizable: false,
                 modal: true,
                 title: "Notebook converted",
                 closeText: "",
                 close: function(event, ui) {$(this).dialog('destroy').remove();},
                 buttons : {
                     "OK": function () {
                         $(this).dialog('close');
                     }
                 },
                 width: 400
             });
         } else if (data.orig_nbformat_minor !== undefined && data.nbformat_minor !== data.orig_nbformat_minor) {
             var that = this;
             var orig_vs = 'v' + data.nbformat + '.' + data.orig_nbformat_minor;
             var this_vs = 'v' + data.nbformat + '.' + this.nbformat_minor;
             msg = "This notebook is version " + orig_vs + ", but we only fully support up to " +
             this_vs + ".  You can still work with this notebook, but some features " +
             "introduced in later notebook versions may not be available."
             
             var dialog = $('<div/>');
             dialog.html(msg);
             this.element.append(dialog);
             dialog.dialog({
                 resizable: false,
                 modal: true,
                 title: "Newer Notebook",
                 closeText: "",
                 close: function(event, ui) {$(this).dialog('destroy').remove();},
                 buttons : {
                     "OK": function () {
                         $(this).dialog('close');
                     }
                 },
                 width: 400
             });
             
         }
         // Create the kernel after the notebook is completely loaded to prevent
         // code execution upon loading, which is a security risk.
         if (! this.read_only) {
             this.start_kernel();
         }
         $([IPython.events]).trigger('notebook_loaded.Notebook');
     };
 
 
     Notebook.prototype.load_notebook_error = function (xhr, textStatus, errorThrow) {
         if (xhr.status === 500) {
             msg = "An error occurred while loading this notebook. Most likely " +
             "this notebook is in a newer format than is supported by this " +
             "version of IPython. This version can load notebook formats " +
             "v"+this.nbformat+" or earlier.";
             var dialog = $('<div/>');
             dialog.html(msg);
             this.element.append(dialog);
             dialog.dialog({
                 resizable: false,
                 modal: true,
                 title: "Error loading notebook",
                 closeText: "",
                 close: function(event, ui) {$(this).dialog('destroy').remove();},
                 buttons : {
                     "OK": function () {
                         $(this).dialog('close');
                     }
                 },
                 width: 400
             });
         }
     }
     
     IPython.Notebook = Notebook;
 
 
     return IPython;
 
 }(IPython));
 

IPython/frontend/html/notebook/static/js/quickhelp.js

@@ -1,71 +1,72 b''
 //----------------------------------------------------------------------------
 //  Copyright (C) 2008-2011  The IPython Development Team
 //
 //  Distributed under the terms of the BSD License.  The full license is in
 //  the file COPYING, distributed as part of this software.
 //----------------------------------------------------------------------------
 
 //============================================================================
 // QuickHelp button
 //============================================================================
 
 var IPython = (function (IPython) {
 
     var QuickHelp = function (selector) {
     };
 
     QuickHelp.prototype.show_keyboard_shortcuts = function () {
         // toggles display of keyboard shortcut dialog
         var that = this;
         if ( this.shortcut_dialog ){
             // if dialog is already shown, close it
             this.shortcut_dialog.dialog("close");
             this.shortcut_dialog = null;
             return;
         }
         var dialog = $('<div/>');
         this.shortcut_dialog = dialog;
         var shortcuts = [
             {key: 'Shift-Enter', help: 'run cell'},
             {key: 'Ctrl-Enter', help: 'run cell in-place'},
+            {key: 'Alt-Enter', help: 'run cell, insert below'},
             {key: 'Ctrl-m x', help: 'cut cell'},
             {key: 'Ctrl-m c', help: 'copy cell'},
             {key: 'Ctrl-m v', help: 'paste cell'},
             {key: 'Ctrl-m d', help: 'delete cell'},
             {key: 'Ctrl-m a', help: 'insert cell above'},
             {key: 'Ctrl-m b', help: 'insert cell below'},
             {key: 'Ctrl-m o', help: 'toggle output'},
             {key: 'Ctrl-m O', help: 'toggle output scroll'},
             {key: 'Ctrl-m l', help: 'toggle line numbers'},
             {key: 'Ctrl-m s', help: 'save notebook'},
             {key: 'Ctrl-m j', help: 'move cell down'},
             {key: 'Ctrl-m k', help: 'move cell up'},
             {key: 'Ctrl-m y', help: 'code cell'},
             {key: 'Ctrl-m m', help: 'markdown cell'},
             {key: 'Ctrl-m t', help: 'raw cell'},
             {key: 'Ctrl-m 1-6', help: 'heading 1-6 cell'},
             {key: 'Ctrl-m p', help: 'select previous'},
             {key: 'Ctrl-m n', help: 'select next'},
             {key: 'Ctrl-m i', help: 'interrupt kernel'},
             {key: 'Ctrl-m .', help: 'restart kernel'},
             {key: 'Ctrl-m h', help: 'show keyboard shortcuts'}
         ];
         for (var i=0; i<shortcuts.length; i++) {
             dialog.append($('<div>').
                 append($('<span/>').addClass('shortcut_key').html(shortcuts[i].key)).
                 append($('<span/>').addClass('shortcut_descr').html(' : ' + shortcuts[i].help))
             );
         };
         dialog.bind('dialogclose', function(event) {
             // dialog has been closed, allow it to be drawn again.
             that.shortcut_dialog = null;
         });
         dialog.dialog({title: 'Keyboard shortcuts', closeText: ''});
     };
 
     // Set module variables
     IPython.QuickHelp = QuickHelp;
 
     return IPython;
 
 }(IPython));

docs/source/interactive/htmlnotebook.txt

@@ -1,432 +1,439 b''
 .. _htmlnotebook:
 
 =========================
 An HTML Notebook IPython
 =========================
 
 .. seealso::
 
     :ref:`Installation requirements <installnotebook>` for the Notebook.
 
 The IPython Notebook consists of two related components:
 
 * An JSON based Notebook document format for recording and distributing
   Python code and rich text.
 * A web-based user interface for authoring and running notebook documents.
 
 The Notebook can be used by starting the Notebook server with the 
 command::
 
     $ ipython notebook
 
 Note that by default, the notebook doesn't load pylab, it's just a normal
 IPython session like any other.  If you want pylab support, you must use::
     
     $ ipython notebook --pylab
 
 which will behave similar to the terminal and Qt console versions, using your
 default matplotlib backend and providing floating interactive plot windows.  If
 you want inline figures, you must manually select the ``inline`` backend::
 
     $ ipython notebook --pylab inline
 
 This server uses the same ZeroMQ-based two process kernel architecture as
 the QT Console as well Tornado for serving HTTP/S requests. Some of the main
 features of the Notebook include:
 
 * Display rich data (png/html/latex/svg) in the browser as a result of
   computations.
 * Compose text cells using HTML and Markdown.
 * Import and export notebook documents in range of formats (.ipynb, .py).
 * In browser syntax highlighting, tab completion and autoindentation.
 * Inline matplotlib plots that can be stored in Notebook documents and opened
   later.
 
 See :ref:`our installation documentation <install_index>` for directions on
 how to install the notebook and its dependencies.
 
 .. note::
 
    You can start more than one notebook server at the same time, if you want to
    work on notebooks in different directories.  By default the first notebook
    server starts in port 8888, later notebooks search for random ports near
    that one.  You can also manually specify the port with the ``--port``
    option.
    
 
 Basic Usage
 ===========
 
 The landing page of the notebook server application, which we call the IPython
 Notebook *dashboard*, shows the notebooks currently available in the directory
 in which the application was started, and allows you to create new notebooks.
 
 A notebook is a combination of two things:
 
 1. An interactive session connected to an IPython kernel, controlled by a web
    application that can send input to the console and display many types of
    output (text, graphics, mathematics and more).  This is the same kernel used
    by the :ref:`Qt console <qtconsole>`, but in this case the web console sends
    input in persistent cells that you can edit in-place instead of the
    vertically scrolling terminal style used by the Qt console.
 
 2. A document that can save the inputs and outputs of the session as well as
    additional text that accompanies the code but is not meant for execution.
    In this way, notebook files serve as a complete computational record of a
    session including explanatory text and mathematics, code and resulting
    figures.  These documents are internally JSON files and are saved with the
    ``.ipynb`` extension.
 
 If you have ever used the Mathematica or Sage notebooks (the latter is also
 web-based__) you should feel right at home.  If you have not, you should be
 able to learn how to use it in just a few minutes.
 
 .. __: http://sagenb.org
 
 
 Creating and editing notebooks
 ------------------------------
 
 You can create new notebooks from the dashboard with the ``New Notebook``
 button or open existing ones by clicking on their name.  Once in a notebook,
 your browser tab will reflect the name of that notebook (prefixed with "IPy:").
 The URL for that notebook is not meant to be human-readable and is *not*
 persistent across invocations of the notebook server.
 
 You can also drag and drop into the area listing files any python file: it
 will be imported into a notebook with the same name (but ``.ipynb`` extension)
 located in the directory where the notebook server was started.  This notebook
 will consist of a single cell with all the code in the file, which you can
 later manually partition into individual cells for gradual execution, add text
 and graphics, etc.
 
 
 Workflow and limitations
 ------------------------
 
 The normal workflow in a notebook is quite similar to a normal IPython session,
 with the difference that you can edit a cell in-place multiple times until you
 obtain the desired results rather than having to rerun separate scripts with
 the ``%run`` magic (though magics also work in the notebook).   Typically
 you'll work on a problem in pieces, organizing related pieces into cells and
 moving forward as previous parts work correctly.  This is much more convenient
 for interactive exploration than breaking up a computation into scripts that
 must be executed together, especially if parts of them take a long time to run
 (In the traditional terminal-based IPython, you can use tricks with namespaces
 and ``%run -i`` to achieve this capability, but we think the notebook is a more
 natural solution for  that kind of problem).
 
 The only significant limitation the notebook currently has, compared to the qt
 console, is that it can not run any code that expects input from the kernel
 (such as scripts that call :func:`raw_input`).  Very importantly, this means
 that the ``%debug`` magic does *not* work in the notebook!  We intend to
 correct this limitation, but in the meantime, there is a way to debug problems
 in the notebook: you can attach a Qt console to your existing notebook kernel,
 and run ``%debug`` from the Qt console.  If your notebook is running on a local
 computer (i.e. if you are accessing it via your localhost address at
 127.0.0.1), you can just type ``%qtconsole`` in the notebook and a Qt console
 will open up connected to that same kernel.
 
 In general, the notebook server prints the full details of how to connect to
 each kernel at the terminal, with lines like::
 
     [IPKernelApp] To connect another client to this kernel, use:
     [IPKernelApp] --existing kernel-3bb93edd-6b5a-455c-99c8-3b658f45dde5.json
 
 This is the name of a JSON file that contains all the port and validation
 information necessary to connect to the kernel.  You can manually start a
 qt console with::
 
     ipython qtconsole --existing kernel-3bb93edd-6b5a-455c-99c8-3b658f45dde5.json
 
 and if you only have a single kernel running, simply typing::
 
     ipython qtconsole --existing
 
 will automatically find it (it will always find the most recently started
 kernel if there is more than one).  You can also request this connection data
 by typing ``%connect_info``; this will print the same file information as well
 as the content of the JSON data structure it contains.
 
     
 Text input
 ----------
 
 In addition to code cells and the output they produce (such as figures), you
 can also type text not meant for execution.  To type text, change the type of a
 cell from ``Code`` to ``Markdown`` by using the button or the :kbd:`Ctrl-m m`
 keybinding (see below).  You can then type any text in Markdown_ syntax, as
 well as mathematical expressions if you use ``$...$`` for inline math or
 ``$$...$$`` for displayed math.
 
 
 Exporting a notebook and importing existing scripts
 ---------------------------------------------------
 
 If you want to provide others with a static HTML or PDF view of your notebook,
 use the ``Print`` button.  This opens a static view of the document, which you
 can print to PDF using your operating system's facilities, or save to a file
 with your web browser's 'Save' option (note that typically, this will create
 both an html file *and* a directory called `notebook_name_files` next to it
 that contains all the necessary style information, so if you intend to share
 this, you must send the directory along with the main html file).
 
 The `Download` button lets you save a notebook file to the Download area
 configured by your web browser (particularly useful if you are running the
 notebook server on a remote host and need a file locally).  The notebook is
 saved by default with the ``.ipynb`` extension and the files contain JSON data
 that is not meant for human editing or consumption.  But you can always export
 the input part of a notebook to a plain python script by choosing Python format
 in the `Download` drop list.  This removes all output and saves the text cells
 in comment areas.  See ref:`below <notebook_format>` for more details on the
 notebook format.
 
 The notebook can also *import* ``.py`` files as notebooks, by dragging and
 dropping the file into the notebook dashboard file list area.  By default, the
 entire contents of the file will be loaded into a single code cell.  But if
 prior to import, you manually add the ``# <nbformat>2</nbformat>`` marker at
 the start and then add separators for text/code cells, you can get a cleaner
 import with the file broken into individual cells.
     
 .. warning::
 
    While in simple cases you can roundtrip a notebook to Python, edit the
    python file and import it back without loss of main content, this is in
    general *not guaranteed to work at all*.  First, there is extra metadata
    saved in the notebook that may not be saved to the ``.py`` format.  And as
    the notebook format evolves in complexity, there will be attributes of the
    notebook that will not survive a roundtrip through the Python form.  You
    should think of the Python format as a way to output a script version of a
    notebook and the import capabilities as a way to load existing code to get a
    notebook started.  But the Python version is *not* an alternate notebook
    format.
 
    
 Importing or executing a notebook as a normal Python file
 ---------------------------------------------------------
 
 The native format of the notebook, a file with a ``.ipynb`` extension, is a
 JSON container of all the input and output of the notebook, and therefore not
 valid Python by itself.  This means that by default, you can not import a
 notebook or execute it as a normal python script.  But if you want use
 notebooks as regular Python files, you can start the notebook server with::
 
   ipython notebook --script
 
 or you can set this option permanently in your configuration file with::
 
     c.NotebookManager.save_script=True
 
 This will instruct the notebook server to save the ``.py`` export of each
 notebook adjacent to the ``.ipynb`` at every save.  These files can be
 ``%run``, imported from regular IPython sessions or other notebooks, or
 executed at the command-line as normal Python files.  Since we export the raw
 code you have typed, for these files to be importable from other code you will
 have to avoid using syntax such as ``%magics`` and other IPython-specific
 extensions to the language.
 
 In regular practice, the standard way to differentiate importable code from the
 'executable' part of a script is to put at the bottom::
 
   if __name__ == '__main__':
     # rest of the code...
 
 Since all cells in the notebook are run as top-level code, you'll need to
 similarly protect *all* cells that you do not want executed when other scripts
 try to import your notebook.  A convenient shortand for this is to define early
 on::
 
   script = __name__ == '__main__'
 
 and then on any cell that you need to protect, use::
 
   if script:
     # rest of the cell...
 
     
 Keyboard use
 ------------
 
 All actions in the notebook can be achieved with the mouse, but we have also
 added keyboard shortcuts for the most common ones, so that productive use of
 the notebook can be achieved with minimal mouse intervention.  The main
 key bindings you need to remember are:
 
 * :kbd:`Shift-Enter`: execute the current cell (similar to the Qt console),
-  show output (if any) and create a new cell below.  Note that in the notebook,
-  simply using :kbd:`Enter` *never* forces execution, it simply inserts a new
-  line in the current cell.  Therefore, in the notebook you must always use
-  :kbd:`Shift-Enter` to get execution (or use the mouse and click on the ``Run
-  Selected`` button).
-
+  show output (if any) and jump to the next cell below. If :kbd:`Shift-Enter` 
+  was invoked on the last input line, a new code cell will also be created. Note 
+  that in the notebook, simply using :kbd:`Enter` *never* forces execution, 
+  it simply inserts a new line in the current cell. Therefore, in the notebook 
+  you must always use :kbd:`Shift-Enter` to get execution (or use the mouse and 
+  click on the ``Run Selected`` button).
+
+* :kbd:`Alt-Enter`: this combination is similar to the previous one, with the 
+  exception that, if the next cell below is not empty, a new code cell will be 
+  added to the notebook, even if the cell execution happens not in the last cell. 
+  In this regard, :kbd:`Alt-Enter`: is simply a shortcut for the :kbd:`Shift-Enter`, 
+  :kbd:`Ctrl-m a` sequence. 
+  
 * :kbd:`Ctrl-Enter`: execute the current cell in "terminal mode", where any
   output is shown but the cursor stays in the current cell, whose input
   area is flushed empty.  This is convenient to do quick in-place experiments
   or query things like filesystem content without creating additional cells you
   may not want saved in your notebook.
 
 * :kbd:`Ctrl-m`: this is the prefix for all other keybindings, which consist
   of an additional single letter.  Type :kbd:`Ctrl-m h` (that is, the sole
   letter :kbd:`h` after :kbd:`Ctrl-m`) and IPython will show you the remaining
   available keybindings.
 
 
 .. _notebook_security:
 
 Security
 ========
 
 You can protect your notebook server with a simple single-password by
 setting the :attr:`NotebookApp.password` configurable. You can prepare a
 hashed password using the function :func:`IPython.lib.security.passwd`:
 
 .. sourcecode:: ipython
 
     In [1]: from IPython.lib import passwd
     In [2]: passwd()
     Enter password: 
     Verify password: 
     Out[2]: 'sha1:67c9e60bb8b6:9ffede0825894254b2e042ea597d771089e11aed'
     
 .. note::
 
   :func:`~IPython.lib.security.passwd` can also take the password as a string
   argument. **Do not** pass it as an argument inside an IPython session, as it
   will be saved in your input history.
 
 You can then add this to your :file:`ipython_notebook_config.py`, e.g.::
 
     # Password to use for web authentication
     c.NotebookApp.password = u'sha1:67c9e60bb8b6:9ffede0825894254b2e042ea597d771089e11aed'
 
 When using a password, it is a good idea to also use SSL, so that your password
 is not sent unencrypted by your browser. You can start the notebook to
 communicate via a secure protocol mode using a self-signed certificate by
 typing::
 
     $ ipython notebook --certfile=mycert.pem
 
 .. note::
 
     A self-signed certificate can be generated with openssl.  For example, the
     following command will create a certificate valid for 365 days with both
     the key and certificate data written to the same file::
 
         $ openssl req -x509 -nodes -days 365 -newkey rsa:1024 -keyout mycert.pem -out mycert.pem
 
 Your browser will warn you of a dangerous certificate because it is
 self-signed.  If you want to have a fully compliant certificate that will not
 raise warnings, it is possible (but rather involved) to obtain one for free,
 `as explained in detailed in this tutorial`__.
 
 .. __: http://arstechnica.com/security/news/2009/12/how-to-get-set-with-a-secure-sertificate-for-free.ars
 	
 Keep in mind that when you enable SSL support, you'll need to access the
 notebook server over ``https://``, not over plain ``http://``.  The startup
 message from the server prints this, but it's easy to overlook and think the
 server is for some reason non-responsive.
 
 
 Quick Howto: running a public notebook server
 =============================================
 
 If you want to access your notebook server remotely with just a web browser,
 here is a quick set of instructions.  Start by creating a certificate file and
 a hashed password as explained above.  Then, create a custom profile for the
 notebook.  At the command line, type::
 
   ipython profile create nbserver
 
 In the profile directory, edit the file ``ipython_notebook_config.py``.  By
 default the file has all fields commented, the minimum set you need to
 uncomment and edit is here::
 
      c = get_config()
 
      # Kernel config
      c.IPKernelApp.pylab = 'inline'  # if you want plotting support always
 
      # Notebook config
      c.NotebookApp.certfile = u'/absolute/path/to/your/certificate/mycert.pem'
      c.NotebookApp.ip = '*'
      c.NotebookApp.open_browser = False
      c.NotebookApp.password = u'sha1:bcd259ccf...your hashed password here'
      # It's a good idea to put it on a known, fixed port
      c.NotebookApp.port = 9999
 
 You can then start the notebook and access it later by pointing your browser to
 ``https://your.host.com:9999`` with ``ipython notebook --profile=nbserver``.
 
 Running with a different URL prefix
 ===================================
 
 The notebook dashboard (i.e. the default landing page with an overview
 of all your notebooks) typically lives at a URL path of
 "http://localhost:8888/". If you want to have it, and the rest of the
 notebook, live under a sub-directory,
 e.g. "http://localhost:8888/ipython/", you can do so with
 configuration options like these (see above for instructions about
 modifying ``ipython_notebook_config.py``)::
 
     c.NotebookApp.base_project_url = '/ipython/'
     c.NotebookApp.base_kernel_url = '/ipython/'
     c.NotebookApp.webapp_settings = {'static_url_prefix':'/ipython/static/'}
 
 .. _notebook_format:
 
 The notebook format
 ===================
 
 The notebooks themselves are JSON files with an ``ipynb`` extension, formatted
 as legibly as possible with minimal extra indentation and cell content broken
 across lines to make them reasonably friendly to use in version-control
 workflows.  You should be very careful if you ever edit manually this JSON
 data, as it is extremely easy to corrupt its internal structure and make the
 file impossible to load.  In general, you should consider the notebook as a
 file meant only to be edited by IPython itself, not for hand-editing.
 
 .. note::
 
      Binary data such as figures are directly saved in the JSON file.  This
      provides convenient single-file portability but means the files can be
      large and diffs of binary data aren't very meaningful.  Since the binary
      blobs are encoded in a single line they only affect one line of the diff
      output, but they are typically very long lines.  You can use the
      'ClearAll' button to remove all output from a notebook prior to
      committing it to version control, if this is a concern.
 
 The notebook server can also generate a pure-python version of your notebook,
 by clicking on the 'Download' button and selecting ``py`` as the format.  This
 file will contain all the code cells from your notebook verbatim, and all text
 cells prepended with a comment marker.  The separation between code and text
 cells is indicated with special comments and there is a header indicating the
 format version.  All output is stripped out when exporting to python.
 
 Here is an example of a simple notebook with one text cell and one code input
 cell, when exported to python format::
 
     # <nbformat>2</nbformat>
 
     # <markdowncell>
 
     # A text cell
 
     # <codecell>
 
     print "hello IPython"
 
 
 Known Issues
 ============
 
 When behind a proxy, especially if your system or browser is set to autodetect
 the proxy, the html notebook might fail to connect to the server's websockets,
 and present you with a warning at startup. In this case, you need to configure
 your system not to use the proxy for the server's address.
 
 In Firefox, for example, go to the Preferences panel, Advanced section,
 Network tab, click 'Settings...', and add the address of the notebook server
 to the 'No proxy for' field.
 
     
 .. _Markdown: http://daringfireball.net/projects/markdown/basics