|
|
# -*- coding: utf-8 -*-
|
|
|
"""Modified input prompt for entering quantities with units.
|
|
|
|
|
|
Modify the behavior of the interactive interpreter to allow direct input of
|
|
|
quantities with units without having to make a function call.
|
|
|
|
|
|
Now the following forms are accepted:
|
|
|
|
|
|
x = 4 m
|
|
|
y = -.45e3 m/s
|
|
|
g = 9.8 m/s**2
|
|
|
a = 2.3 m/s^2 # ^ -> ** automatically
|
|
|
|
|
|
All other input is processed normally.
|
|
|
|
|
|
Authors
|
|
|
-------
|
|
|
- Fernando Perez <Fernando.Perez@berkeley.edu>
|
|
|
"""
|
|
|
#*****************************************************************************
|
|
|
# Copyright (C) 2008-2009 The IPython Development Team
|
|
|
# Copyright (C) 2001-2007 Fernando Perez <fperez@colorado.edu>
|
|
|
#
|
|
|
# Distributed under the terms of the BSD License. The full license is in
|
|
|
# the file COPYING, distributed as part of this software.
|
|
|
#*****************************************************************************
|
|
|
|
|
|
# This file is an example of how to modify IPython's line-processing behavior
|
|
|
# without touching the internal code. We'll define an alternate pre-processing
|
|
|
# stage which allows a special form of input (which is invalid Python syntax)
|
|
|
# for certain quantities, rewrites a line of proper Python in those cases, and
|
|
|
# then passes it off to IPython's normal processor for further work.
|
|
|
|
|
|
# With this kind of customization, IPython can be adapted for many
|
|
|
# special-purpose scenarios providing alternate input syntaxes.
|
|
|
|
|
|
# This file can be imported like a regular module.
|
|
|
|
|
|
# IPython has a prefilter() function that analyzes each input line. We redefine
|
|
|
# it here to first pre-process certain forms of input
|
|
|
|
|
|
# The prototype of any alternate prefilter must be like this one (the name
|
|
|
# doesn't matter):
|
|
|
# - line is a string containing the user input line.
|
|
|
# - continuation is a parameter which tells us if we are processing a first line of
|
|
|
# user input or the second or higher of a multi-line statement.
|
|
|
|
|
|
def prefilter_PQ(self,line,continuation):
|
|
|
"""Alternate prefilter for input of PhysicalQuantityInteractive objects.
|
|
|
|
|
|
This assumes that the function PhysicalQuantityInteractive() has been
|
|
|
imported."""
|
|
|
|
|
|
from re import match
|
|
|
from IPython.core.iplib import InteractiveShell
|
|
|
|
|
|
# This regexp is what does the real work
|
|
|
unit_split = match(r'\s*(\w+)\s*=\s*(-?\d*\.?\d*[eE]?-?\d*)\s+([a-zA-Z].*)',
|
|
|
line)
|
|
|
|
|
|
# If special input was ecnountered, process it:
|
|
|
if unit_split:
|
|
|
var,val,units = unit_split.groups()
|
|
|
if var and val and units:
|
|
|
units = units.replace('^','**')
|
|
|
# Now a valid line needs to be constructed for IPython to process:
|
|
|
line = var +" = PhysicalQuantityInteractive(" + val + ", '" + \
|
|
|
units + "')"
|
|
|
#print 'New line:',line # dbg
|
|
|
|
|
|
# In the end, always call the default IPython _prefilter() function. Note
|
|
|
# that self must be passed explicitly, b/c we're calling the unbound class
|
|
|
# method (since this method will overwrite the instance prefilter())
|
|
|
return InteractiveShell._prefilter(self,line,continuation)
|
|
|
|
|
|
# Rebind this to be the new IPython prefilter:
|
|
|
from IPython.core.iplib import InteractiveShell
|
|
|
InteractiveShell.prefilter = prefilter_PQ
|
|
|
|
|
|
# Clean up the namespace.
|
|
|
del InteractiveShell,prefilter_PQ
|
|
|
|
|
|
# Just a heads up at the console
|
|
|
print '*** Simplified input for physical quantities enabled.'
|
|
|
|
