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Created January 8, 2012 21:05
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IPython 0.0.1, a simple script to be loaded as $PYTHONSTARTUP: of historical interest only...
#!/usr/bin/env python
Interactive execution with automatic history, tries to mimic Mathematica's
prompt system. This environment's main features are:
- Numbered prompts (In/Out) similar to Mathematica. Only actions that produce
output (NOT assingments, for example) affect the counter and cache.
- The following GLOBAL variables always exist (so don't overwrite them!):
_p: stores previous result which generated printable output.
_pp: next previous
_ppp: next-next previous
_cache[]: cache of all previous output, indexed by prompt counter.
_pc: short alias for _cache
- Global variables named _p<n> are dynamically created (<n> being the
prompt counter), such that the following is always true:
_p<n> == _pc[<n>]
E.g. the 4th result is always available as either _pc[4] or as _p4.
Use help() to open Python's builtin help system, which can also be
called with optional keywords as arguments.
If you are running inside an Emacs buffer, use doc() as dumb-terminal
simpler version of help() [doesn't do all that help() does, though].
Current configuration (set _load.. variables to 0 to turn off):
Control loading of Numerical Python modules: _load_Numeric = %(_load_Numeric)s
Gnuplot Globals GP and gp (module/instance): _load_Gnuplot = %(_load_Gnuplot)s
Load gracePlot (2D-plotting only) : _load_gracePlot = %(_load_gracePlot)s
Globals for SI units (including g=9.8) : _load_units = %(_load_units)s
Starting number for prompt counter : _prompt_ini = %(_prompt_ini)s
Number of history items to store in cache : _cache_size = %(_cache_size)s """
# Configure here
_load_Numeric = 1
_load_Gnuplot = 1
_load_gracePlot = 1
_load_units = 1
_cache_size = 1000
_prompt_ini = 1
# *** Don't modify below unless you know what you're doing. ***
# Crude first version, with minimal object structure. This could be done much
# better, by defining a Cache class (probably using weak references or
# generators). But it seems to work ok. Haven't checked for memory circularity
# problems, though.
# Copyright (C) 2001 Fernando Pérez. <>
# Distributed under the terms of the GNU General Public License.
# The full text of the GPL is available at:
__author__ = 'Fernando Pérez. <>'
__version__= '0.1'
# Class definitions
class _HistPrompt1:
"""Simple interactive prompt like Mathematica's."""
def __str__(self):
return '\nIn['+`_prompt_count`+']:= '
class _HistPrompt2:
"""Simple interactive continuation prompt."""
def __str__(self):
return '...'+' '*(len('In['+`_prompt_count`+']:= ')-3)
# Function definitions
def _history_print(arg):
"""Printing with history cache management.
This is invoked everytime the interpreter needs to print, and is activated
by setting the variable sys.displayhook to it."""
global _p,_pp,_ppp,_cache,_prompt_count
# cleanup cache if needed
if _prompt_count > _cache_size:
print '\nWARNING: History cache size limit (currently '+\
`_cache_size`+') hit.'
print 'Flushing cache and resetting history counter...'
print 'The only history variable available will be _p with current result.'
print 'Increase the variable _cache_size if you need a larger cache.'
_prompt_count = _prompt_ini
_cache = []
_p,_pp,_ppp = '','',''
# fill bottom of cache if initial offset is not zero
for n in range(_prompt_ini): _cache.append(None)
# delete auto-generated vars from global namespace
for n in range(_prompt_ini,_cache_size):
exec 'del _p'+`n` in globals()
# update cache
_ppp = _pp
_pp = _p
_p = arg
exec '_p'+`_prompt_count`+'=_cache[-1]' in globals()
print '\nOut['+`_prompt_count`+']=',arg
_prompt_count += 1
# end of _history_print()
def intro():
"""Show global docstring and config info."""
print __doc__ % globals()
def dgrep(pat,*opts):
"""Return grep() on dir()+dir(__builtins__).
A very common use of grep() when working interactively."""
exec 'data = dir()+dir(__builtins__)' in globals()
return grep(pat,data,*opts)
# end of dgrep()
def idgrep(pat):
"""Case-insensitive dgrep()"""
exec 'data = dir()+dir(__builtins__)' in globals()
return grep(pat,data,case=0)
# end of dgrep()
def Gnuplot_setup():
"""Setup some convenient globals for Gnuplot plotting, including a global
gp Gnuplot object, ready for use."""
global GP,gp
GP = Gnuplot
gp = GP.Gnuplot() # global plotting process
gp.logx = 'set logscale x'
gp.logy = 'set logscale y'
gp.nolog = 'set nologscale'
gp.points = 'set data style points'
gp.lines = 'set data style lines'
gp.linesp = 'set data style linespoints'
gp.errorbars = 'set data style errorbars'
# end of Gnuplot_setup()
def SI_Units():
"""Define some globals for physical units and constants.
The following become available:
These can be overwritten at any time. Calling SI_Units() again will reset
their values if needed. """
global g,mm,cm,km,gm,s,sec,hr,day,year,deg,ft,lb,inch
# physical constants
g = 9.8
# units
mm = 0.001 # length
cm = 0.01
km = 1000.
gm = 0.001 # mass
s,sec = 1.,1. # time
hr = 3600.
day = 24*hr
year = 365*day
deg = pi/180. # angles
inch = 0.0254 # british
ft = 12*inch
lb = 0.454
# end of SI_Units()
def import_fail_info(mod_name):
"""Inform load failure for a module."""
print """
WARNING: Loading of %(mod_name)s-related modules failed.
Fix your configuration or set _load_%(mod_name)s to 0 to prevent
seeing this message every time.
""" % vars()
# Setup everything at global level for history system to work
# Python standard modules
import sys
from math import *
# Other modules
from Itpl import Itpl # available at
from genutils import *
# User-controlled modules and globals-affecting functions
if _load_Numeric:
from Numeric import * # Numeric *must* come after math.
from numutils import *
# useful for testing infinities in results of array divisions
# (which don't raise an exception)
infty = Infinity = (array([1])/0.0)[0]
if _load_Gnuplot:
import Gnuplot
if _load_gracePlot:
from gracePlot import gracePlot
if _load_units:
# pydoc doesn't exist in Python 2.0 (I think):
from pydoc import help
print "Module pydoc not found. help() function unavailable."
# Initialize cache
_p,_pp,_ppp = '','',''
_prompt_count = _prompt_ini
_pc = _cache = [] # _pc is just an alias
# fill bottom of cache if initial offset is not zero
for n in range(_prompt_ini): _cache.append(None)
# cleanup global namespace a bit
del import_fail_info,n
# Set in/out prompts and printing system
sys.displayhook = _history_print
sys.ps1 = _HistPrompt1()
sys.ps2 = _HistPrompt2()
# Startup info
print '\nPython',sys.version.split('\n')[0]
print '\nInteractive Python -- Type intro() for a brief explanation.'
#************************* end of file <> ***********************
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