isympy(1)isympy(1)NAMEisympy - interactive shell for SymPy
SYNOPSISisympy [-c | --console] [-p ENCODING | --pretty ENCODING] [-t TYPE |
--types TYPE] [-o ORDER | --order ORDER] [-q | --quiet] [-d |
--doctest] [-C | --no-cache] [-a | --auto] [-D | --debug] [ -- |
PYTHONOPTIONS]
isympy [ {-h | --help} | {-v | --version} ]
DESCRIPTIONisympy is a Python shell for SymPy. It is just a normal python shell
(ipython shell if you have the ipython package installed) that executes
the following commands so that you don't have to:
>>> from __future__ import division
>>> from sympy import *
>>> x, y, z = symbols("x,y,z")
>>> k, m, n = symbols("k,m,n", integer=True)
So starting isympy is equivalent to starting python (or ipython) and
executing the above commands by hand. It is intended for easy and quick
experimentation with SymPy. For more complicated programs, it is recom‐
mended to write a script and import things explicitly (using the "from
sympy import sin, log, Symbol, ..." idiom).
OPTIONS-c SHELL, --console=SHELL
Use the specified shell (python or ipython) as console backend
instead of the default one (ipython if present or python other‐
wise).
Example: isympy-c python
SHELL could be either 'ipython' or 'python'
-p ENCODING, --pretty=ENCODING
Setup pretty printing in SymPy. By default, the most pretty,
unicode printing is enabled (if the terminal supports it). You
can use less pretty ASCII printing instead or no pretty printing
at all.
Example: isympy-p no
ENCODING must be one of 'unicode', 'ascii' or 'no'.
-t TYPE, --types=TYPE
Setup the ground types for the polys. By default, gmpy ground
types are used if gmpy2 or gmpy is installed, otherwise it falls
back to python ground types, which are a little bit slower. You
can manually choose python ground types even if gmpy is in‐
stalled (e.g., for testing purposes).
Note that sympy ground types are not supported, and should be
used only for experimental purposes.
Note that the gmpy1 ground type is primarily intended for test‐
ing; it the use of gmpy even if gmpy2 is available.
This is the same as setting the environment variable
SYMPY_GROUND_TYPES to the given ground type (e.g.,
SYMPY_GROUND_TYPES='gmpy')
The ground types can be determined interactively from the vari‐
able sympy.polys.domains.GROUND_TYPES inside the isympy shell
itself.
Example: isympy-t python
TYPE must be one of 'gmpy', 'gmpy1' or 'python'.
-o ORDER, --order=ORDER
Setup the ordering of terms for printing. The default is lex,
which orders terms lexicographically (e.g., x**2 + x + 1). You
can choose other orderings, such as rev-lex, which will use re‐
verse lexicographic ordering (e.g., 1 + x + x**2).
Note that for very large expressions, ORDER='none' may speed up
printing considerably, with the tradeoff that the order of the
terms in the printed expression will have no canonical order
Example: isympy-o rev-lax
ORDER must be one of 'lex', 'rev-lex', 'grlex', 'rev-grlex',
'grevlex', 'rev-grevlex', 'old', or 'none'.
-q, --quiet
Print only Python's and SymPy's versions to stdout at startup,
and nothing else.
-d, --doctest
Use the same format that should be used for doctests. This is
equivalent to 'isympy -c python -p no'.
-C, --no-cache
Disable the caching mechanism. Disabling the cache may slow cer‐
tain operations down considerably. This is useful for testing
the cache, or for benchmarking, as the cache can result in de‐
ceptive benchmark timings.
This is the same as setting the environment variable
SYMPY_USE_CACHE to 'no'.
-a, --auto
Automatically create missing symbols. Normally, typing a name of
a Symbol that has not been instantiated first would raise
NameError, but with this option enabled, any undefined name will
be automatically created as a Symbol. This only works in IPython
0.11.
Note that this is intended only for interactive, calculator
style usage. In a script that uses SymPy, Symbols should be in‐
stantiated at the top, so that it's clear what they are.
This will not override any names that are already defined, which
includes the single character letters represented by the mnemon‐
ic QCOSINE (see the "Gotchas and Pitfalls" document in the docu‐
mentation). You can delete existing names by executing "del
name" in the shell itself. You can see if a name is defined by
typing "'name' in globals()".
The Symbols that are created using this have default assump‐
tions. If you want to place assumptions on symbols, you should
create them using symbols() or var().
Finally, this only works in the top level namespace. So, for ex‐
ample, if you define a function in isympy with an undefined Sym‐
bol, it will not work.
-D, --debug
Enable debugging output. This is the same as setting the envi‐
ronment variable SYMPY_DEBUG to 'True'. The debug status is set
in the variable SYMPY_DEBUG within isympy.
-- PYTHONOPTIONS
These options will be passed on to ipython (1) shell. Only sup‐
ported when ipython is being used (standard python shell not
supported).
Two dashes (--) are required to separate PYTHONOPTIONS from the
other isympy options.
For example, to run iSymPy without startup banner and colors:
isympy-q -c ipython -- --colors=NoColor
-h, --help
Print help output and exit.
-v, --version
Print isympy version information and exit.
FILES
${HOME}/.sympy-history
Saves the history of commands when using the python shell as
backend.
BUGS
The upstreams BTS can be found at ⟨https://github.com/sympy/sympy/is‐
sues⟩ Please report all bugs that you find in there, this will help im‐
prove the overall quality of SymPy.
SEE ALSOipython(1), python(1)
2007-10-8 isympy(1)
