examples/IPython Kernel/Terminal Usage.ipynb

{
 "metadata": {
  "name": "",
  "signature": "sha256:993106eecfd7abe1920e1dbe670c4518189c26e7b29dcc541835f7dcf6fffbb2"
 },
 "nbformat": 3,
 "nbformat_minor": 0,
 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "A few things that work best/only at the IPython terminal or Qt console clients"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "## Running code with `%run`"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "%%writefile script.py\n",
      "x = 10\n",
      "y = 20\n",
      "z = x+y\n",
      "print 'z is:', z"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Writing script.py\n"
       ]
      }
     ],
     "prompt_number": 1
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "%run script"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "z is: 30\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "x"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 3,
       "text": [
        "10"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Event loop and GUI integration"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "The `%gui` magic enables the integration of GUI event loops with the interactive execution loop, allowing you to run GUI code without blocking IPython.\n",
      "\n",
      "Consider for example the execution of Qt-based code. Once we enable the Qt gui support:"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "%gui qt"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 4
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "We can define a simple Qt application class (simplified version from [this Qt tutorial](http://zetcode.com/tutorials/pyqt4/firstprograms)):"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import sys\n",
      "from PyQt4 import QtGui, QtCore\n",
      "\n",
      "class SimpleWindow(QtGui.QWidget):\n",
      "    def __init__(self, parent=None):\n",
      "        QtGui.QWidget.__init__(self, parent)\n",
      "\n",
      "        self.setGeometry(300, 300, 200, 80)\n",
      "        self.setWindowTitle('Hello World')\n",
      "\n",
      "        quit = QtGui.QPushButton('Close', self)\n",
      "        quit.setGeometry(10, 10, 60, 35)\n",
      "\n",
      "        self.connect(quit, QtCore.SIGNAL('clicked()'),\n",
      "                     self, QtCore.SLOT('close()'))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 5
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "And now we can instantiate it:"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "app = QtCore.QCoreApplication.instance()\n",
      "if app is None:\n",
      "    app = QtGui.QApplication([])\n",
      "\n",
      "sw = SimpleWindow()\n",
      "sw.show()\n",
      "\n",
      "from IPython.lib.guisupport import start_event_loop_qt4\n",
      "start_event_loop_qt4(app)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 6
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "But IPython still remains responsive:"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "10+2"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 7,
       "text": [
        "12"
       ]
      }
     ],
     "prompt_number": 7
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "The `%gui` magic can be similarly used to control Wx, Tk, glut and pyglet applications, [as can be seen in our examples](https://github.com/ipython/ipython/tree/master/examples/lib)."
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Embedding IPython in a terminal application"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "%%writefile simple-embed.py\n",
      "# This shows how to use the new top-level embed function.  It is a simpler\n",
      "# API that manages the creation of the embedded shell.\n",
      "\n",
      "from IPython import embed\n",
      "\n",
      "a = 10\n",
      "b = 20\n",
      "\n",
      "embed(header='First time', banner1='')\n",
      "\n",
      "c = 30\n",
      "d = 40\n",
      "\n",
      "embed(header='The second time')"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Writing simple-embed.py\n"
       ]
      }
     ],
     "prompt_number": 12
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "The example in kernel-embedding shows how to embed a full kernel into an application and how to connect to this kernel from an external process."
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Logging terminal sessions and transitioning to a notebook"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "The `%logstart` magic lets you log a terminal session with various degrees of control, and the `%notebook` one will convert an interactive console session into a notebook with all input cells already created for you (but no output)."
     ]
    }
   ],
   "metadata": {}
  }
 ]
}