Tribblix: manual page: isympy.1

isympy(1) isympy(1)

NAME

isympy - interactive shell for SymPy

SYNOPSIS

isympy
[-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} ]

DESCRIPTION

isympy 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 recommended 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
otherwise).

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 installed (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
testing; 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
variable 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
reverse 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
certain operations down considerably. This is useful for
testing the cache, or for benchmarking, as the cache can
result in deceptive 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
instantiated 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
mnemonic QCOSINE (see the "Gotchas and Pitfalls" document in
the documentation). 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
assumptions. 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
example, if you define a function in isympy with an undefined
Symbol, it will not work.

-D, --debug
Enable debugging output. This is the same as setting the
environment 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
supported 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