Miscellaneous Additions #179

ShikharJ · 2017-07-29T11:53:18Z

No description provided.

ShikharJ · 2017-07-29T11:56:13Z

symengine/lib/symengine_wrapper.pyx

@@ -2977,11 +2979,16 @@ zoo = c2py(symengine.ComplexInf)
 nan = c2py(symengine.Nan)
 true = c2py(symengine.boolTrue)
 false = c2py(symengine.boolFalse)
+try:
+    import sympy
+    hbar = PyFunction(sympy.hbar, (), sympy.hbar.func, sympy_module)


@isuruf This seemingly doesn't work as it returns:

'module' object has no attribute 'hbar'

I tried changing this to:

PyFunction(sympy.physics.quantum.constants.HBar, (), sympy.physics.quantum.constants.HBar.func, sympy_module)

but even that returns:

'module' object has no attribute 'physics'

Ping @isuruf

How is hbar imported in sympy?

Through sympy.physics.quantum.constants

No, I mean the exact statement

Why don't you try that then?

See my comment here. Changing to hbar makes no difference as well.

You mean from sympy.physics.quantum.constants import hbar or sympy.hbar?

This:

PyFunction(sympy.physics.quantum.constants.hbar, (), sympy.physics.quantum.constants.hbar.func, sympy_module)

I meant this,

from sympy.physics.quantum.constants import hbar as hbar_sympy PyFunction(hbar_sympy, (), hbar_sympy, sympy_module)

isuruf · 2017-07-31T13:18:48Z

symengine/lib/symengine_wrapper.pyx

@@ -2977,11 +3029,16 @@ zoo = c2py(symengine.ComplexInf)
 nan = c2py(symengine.Nan)
 true = c2py(symengine.boolTrue)
 false = c2py(symengine.boolFalse)
+try:
+    import sympy


This adds sympy's initialization time to symengine's initialization time. That should be avoided.

How are you going to use hbar in sympy? sympy.physics would import from sympy.core.backend which would in turn import from sympy.physics for hbar if USE_SYMENGINE=1.

I meant, in certain places there's code like this:

return exp(-I*self.position*bra.momentum/hbar)/sqrt(2*pi*hbar)

which gives the error:

Cannot convert `hbar` to a symengine type.

in sympy.physics

Say you define hbar in symengine. What changes are you going to do in sympy?

If hbar as an object under class Constant is defined in SymEngine, I'd follow the same routine that we follow for all the other objects. That's why I asked for implementing the same in the Gitter channel.

No, it's not the same as others. hbar is not defined in sympy.core, but in sympy.physics.
sympy.physics would import from sympy.core.backend which would in turn import from sympy.physics for hbar if USE_SYMENGINE=1 leading to a cyclic dependency

Would it be possible to define hbar in sympy.physics using PyFunction? That way I think, we could have a check for USE_SYMENGINE=1 in the respective modules and define hbar if the condition is true?

SymPy developers are of the opinion that only imports should change and USE_SYMENGINE=1 should be used in sympy.core.backend only.
For this case, I think you'd have to write a new class NumberSymbol that is a child class of Constant and do something like what NumberWrapper does.

I'll do that in another PR. Thanks for clarifying my doubts.

isuruf · 2017-07-31T13:21:46Z

symengine/lib/symengine_wrapper.pyx

+    def copy(self):
+        return self.func(*self.args)
+
+    def xreplace(self, rule):


This is already defined.

isuruf · 2017-07-31T13:22:30Z

symengine/lib/symengine_wrapper.pyx

+        value, _ = self._xreplace(rule)
+        return value
+
+    def _xreplace(self, rule):


This method is slow. Use subs to do this and check that the result is different.

I cross checked again, this isn't needed at all in the latest master of SymPy.

ShikharJ · 2017-08-03T14:08:25Z

@isuruf The implementation work here is done. Can you review? I'll add the attributes and NumberSymbol class in another PR.

isuruf · 2017-08-03T14:14:23Z

symengine/lib/symengine_wrapper.pyx

+class AssocOp(Basic):
+
+    @classmethod
+    def _from_args(cls, args):


This is untested.

isuruf · 2017-08-03T14:15:29Z

symengine/lib/symengine_wrapper.pyx

@@ -689,7 +689,7 @@ cdef class Basic(object):
        elif (op == 5):
            return c2py(<RCP[const symengine.Basic]>(symengine.Ge(A.thisptr, B.thisptr)))

-    def expand(Basic self not None):
+    def expand(Basic self not None, *args, **kwargs):


Having this ignore parameters is not good. We should implement them.

The actual issue that I was facing was that during the use of exp in SymPy, the associated object was making a call like:

e.expand(complex=True)

I don't think the expansion for complex domain has been implemented in SymEngine for now. What do you suggest we do?

Ping @isuruf.

As I mentioned we should implement them. Accepting any argument and doing nothing is worse than throwing an error, because it may suggest to the user that it is allowed.

I could not find how SymPy handles complex expansion. I tried introducing keywords in Pow and the trigonometric functions, but the parser is throwing up issues. I think it would be better if these were handled later, as it would take up a lot of time right now. I'm dropping the commit. These are required only for a single import in SymPy.

ShikharJ · 2017-08-10T10:50:22Z

@isuruf Can you help me in fixing the current error log here as well?

isuruf · 2017-08-10T11:30:44Z

symengine/lib/symengine_wrapper.pyx

@@ -825,6 +825,9 @@ cdef class Basic(object):
    def is_Matrix(self):
        return False

+    def copy(self):
+        return self.__class__(*self.args)


I'm not sure what the usage of copy is since this object is immutable.

This directly follows from SymPy's implementation of Basic. Should I remove it then?

Just return self

ShikharJ · 2017-08-13T07:32:45Z

@sumith1896 @certik Can you review and merge this please?

sumith1896 · 2017-08-13T11:57:43Z

I'm having a look

isuruf · 2017-08-17T14:53:00Z

symengine/lib/symengine_wrapper.pyx

@@ -787,6 +787,30 @@ cdef class Basic(object):

    evalf = n

+    def matches(self, expr, repl_dict={}, old=False):


Please implement this in symengine, not symengine.py

ShikharJ · 2017-08-18T12:48:11Z

@isuruf I've taken a note of the changes for further improvement. Can you review and merge this? We'll need to have a release in SymEngine and SymEngine.py to make our changes apparent in SymPy. I'll push in the PRs for different directories as soon as that is done.

isuruf · 2017-08-18T13:17:34Z

We'll use a dev commit for SymPy testing. I don't want to make a release in a rush

ShikharJ · 2017-08-18T16:01:11Z

Ok, so can I have a review of this?

ShikharJ commented Jul 29, 2017

View reviewed changes

isuruf reviewed Jul 31, 2017

View reviewed changes

ShikharJ force-pushed the Misc branch 5 times, most recently from a96221b to a57676e Compare August 3, 2017 13:46

isuruf reviewed Aug 3, 2017

View reviewed changes

ShikharJ force-pushed the Misc branch 3 times, most recently from 4d31d7a to 1c0a50c Compare August 10, 2017 10:35

ShikharJ added 4 commits August 10, 2017 16:57

Class AssocOp and methods _from_args and make_args

02c3944

Basic attribute copy()

6af893e

Attributes for Integer and Rational Class

d94fdc0

Minor Improvement to Sympification of Tuples and Lists

7d142ae

isuruf reviewed Aug 10, 2017

View reviewed changes

ShikharJ force-pushed the Misc branch 3 times, most recently from 87e8559 to a25dfbe Compare August 12, 2017 13:10

Pow attributes base and exp

a3fa1f1

ShikharJ force-pushed the Misc branch from a25dfbe to 3aba342 Compare August 13, 2017 07:27

isuruf reviewed Aug 17, 2017

View reviewed changes

Added Tests

add40b1

ShikharJ force-pushed the Misc branch from 4a12658 to add40b1 Compare August 18, 2017 12:43

isuruf merged commit 169ba50 into symengine:master Aug 19, 2017

ShikharJ deleted the Misc branch August 19, 2017 16:04

		@@ -787,6 +787,30 @@ cdef class Basic(object):

		evalf = n

		def matches(self, expr, repl_dict={}, old=False):

Miscellaneous Additions #179

Miscellaneous Additions #179

Uh oh!

Conversation

ShikharJ commented Jul 29, 2017

Uh oh!

ShikharJ Jul 29, 2017 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

ShikharJ Jul 31, 2017 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

isuruf Jul 31, 2017 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

ShikharJ commented Aug 3, 2017 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

ShikharJ Aug 10, 2017 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

ShikharJ commented Aug 10, 2017

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

ShikharJ Jul 29, 2017 •

edited

Loading

ShikharJ Jul 31, 2017 •

edited

Loading

isuruf Jul 31, 2017 •

edited

Loading

ShikharJ commented Aug 3, 2017 •

edited

Loading

ShikharJ Aug 10, 2017 •

edited

Loading