Am 30.03.2015 um 21:33 schrieb Aaron Meurer:
I would definitely test the different alternatives for sympy.abc to
see what's faster.
I just ran bin/test with `a = Symbol('a')` etc.
Runtime went from 56:29 to 56:37, i.e. below the noise threshold.
That was with Python 2.7. I guess the Pyton
Symbols are cached by name and assumptions, and like everything else in
SymPy, are immutable. Thus:
In [1]: a = symbols('a')
In [2]: a2 = symbols('a', positive=True)
In [3]: a is a2
Out[3]: False
In [4]: hash(a) == hash(a2)
Out[4]: False
So no, you should have no problems with assumptions.
Performance:
Using symbols() in all contexts might have performance ramifications,
creating new Symbol() objects means more memory pressure than reusing
precreated symbols from sympy.abc (which happen 521 times in SymPy
itself, hopefully just in test code).
We cache symbol creation,
Am 02.04.2015 um 18:46 schrieb James Crist:
Performance:
Using symbols() in all contexts might have performance ramifications,
creating new Symbol() objects means more memory pressure than reusing
precreated symbols from sympy.abc (which happen 521 times in SymPy
itself, hopefully just in
Hi all,
I'm wondering about the section on creating symbols in
https://github.com/sympy/sympy/wiki/Idioms-and-Antipatterns#strings-as-input
.
It is mildly discouraging importing from sympy.abc because an accidental
from sympy.abc import * would clobber I and Q (and possibly others),
and
On Mon, Mar 30, 2015 at 4:26 AM, Joachim Durchholz j...@durchholz.org wrote:
Hi all,
I'm wondering about the section on creating symbols in
https://github.com/sympy/sympy/wiki/Idioms-and-Antipatterns#strings-as-input
.
It is mildly discouraging importing from sympy.abc because an accidental
I would definitely test the different alternatives for sympy.abc to
see what's faster.
Also, I wonder what the effect of sympy.abc on the cache is. We have
an LRU cache, and assumedly importing it messes with that, at least
for a little bit.
Aaron Meurer
On Mon, Mar 30, 2015 at 1:52 PM, Joachim
Am 30.03.2015 um 19:58 schrieb Aaron Meurer:
symbols() supports commas, so an easy thing to do here is to use the
form symbols(' t, w, x, y, z, n, k, m, p, i'), so that the left-hand
side of the assignment exactly matches the right-hand side.
Ah, I knew it could do commas but I didn't know
Am 30.03.2015 um 21:33 schrieb Aaron Meurer:
I would definitely test the different alternatives for sympy.abc to
see what's faster.
Also, I wonder what the effect of sympy.abc on the cache is. We have
an LRU cache, and assumedly importing it messes with that, at least
for a little bit.
