Since this seems to break only when the function name is "phi", this
looks like an instance of https://github.com/sympy/sympy/issues/6938.
But I'm not quite sure what other SymPy function is named "phi". I
didn't find any in a quick grep.

Aaron Meurer

On Thu, Mar 10, 2016 at 1:54 PM, Sartaj Singh <[email protected]> wrote:
> Apparently, this also does not work,
>
> # leosartaj at Mothership in ~/projects/sympy on git:master o [0:09:48]
> $ isympy
> IPython console for SymPy 1.0.1.dev (Python 2.7.11-64-bit) (ground types:
> python)
>
> These commands were executed:
>>>> from __future__ import division
>>>> from sympy import *
>>>> x, y, z, t = symbols('x y z t')
>>>> k, m, n = symbols('k m n', integer=True)
>>>> f, g, h = symbols('f g h', cls=Function)
>>>> init_printing()
>
> Documentation can be found at http://docs.sympy.org/dev
>
> In [1]: phi = symbols('phi', cls=Function)
>
> In [2]: phi(5.0)
> ---------------------------------------------------------------------------
> TypeError                                 Traceback (most recent call last)
> <ipython-input-2-68868fcc8946> in <module>()
> ----> 1 phi(5.0)
>
> /home/leosartaj/projects/sympy/sympy/core/function.pyc in __new__(cls,
> *args, **options)
>     718     def __new__(cls, *args, **options):
>     719         args = list(map(sympify, args))
> --> 720         obj = super(AppliedUndef, cls).__new__(cls, *args,
> **options)
>     721         return obj
>     722
>
> /home/leosartaj/projects/sympy/sympy/core/cache.pyc in wrapper(*args,
> **kwargs)
>      93                     retval = cfunc(*args, **kwargs)
>      94                 except TypeError:
> ---> 95                     retval = func(*args, **kwargs)
>      96                 return retval
>      97
>
> /home/leosartaj/projects/sympy/sympy/core/function.pyc in __new__(cls,
> *args, **options)
>     390         pr2 = min(cls._should_evalf(a) for a in result.args)
>     391         if pr2 > 0:
> --> 392             return result.evalf(mlib.libmpf.prec_to_dps(pr))
>     393         return result
>     394
>
> /home/leosartaj/projects/sympy/sympy/core/evalf.pyc in evalf(self, n, subs,
> maxn, chop, strict, quad, verbose)
>    1384             options['quad'] = quad
>    1385         try:
> -> 1386             result = evalf(self, prec + 4, options)
>    1387         except NotImplementedError:
>    1388             # Fall back to the ordinary evalf
>
> /home/leosartaj/projects/sympy/sympy/core/evalf.pyc in evalf(x, prec,
> options)
>    1282             if 'subs' in options:
>    1283                 x = x.subs(evalf_subs(prec, options['subs']))
> -> 1284             xe = x._eval_evalf(prec)
>    1285             re, im = xe.as_real_imag()
>    1286             if re.has(re_) or im.has(im_):
>
> /home/leosartaj/projects/sympy/sympy/core/function.pyc in _eval_evalf(self,
> prec)
>     501
>     502         with mpmath.workprec(prec):
> --> 503             v = func(*args)
>     504
>     505         return Expr._from_mpmath(v, prec)
>
> /home/leosartaj/anaconda/envs/my/lib/python2.7/site-packages/mpmath/ctx_mp_python.pyc
> in __call__(self, prec, dps, rounding)
>     344         if not rounding: rounding = rounding2
>     345         if dps: prec = dps_to_prec(dps)
> --> 346         return self.context.make_mpf(self.func(prec, rounding))
>     347
>     348     @property
>
> /home/leosartaj/anaconda/envs/my/lib/python2.7/site-packages/mpmath/libmp/libelefun.pyc
> in f(prec, rnd)
>     114     def f(prec, rnd=round_fast):
>     115         wp = prec + 20
> --> 116         v = fixed(wp)
>     117         if rnd in (round_up, round_ceiling):
>     118             v += 1
>
> /home/leosartaj/anaconda/envs/my/lib/python2.7/site-packages/mpmath/libmp/libelefun.pyc
> in g(prec, **kwargs)
>      95         memo_prec = f.memo_prec
>      96         if prec <= memo_prec:
> ---> 97             return f.memo_val >> (memo_prec-prec)
>      98         newprec = int(prec*1.05+10)
>      99         f.memo_val = f(newprec, **kwargs)
>
> TypeError: unsupported operand type(s) for >>: 'long' and 'mpf'
>
>
> This does work though,
>
>>>> phi(5)
> φ(5)
>
> However,
>
>>>> p = symbols('p', cls=Function)
>>>>  p(5.0)
> p(5.0)
>
>>>> p(t).xreplace({t: 5.0})
> p(5.0) # works without any problems
>
>
> By My understanding, is symbols with cls=Function arg not expected to make
> an undefined function?
>
>
> On Friday, 11 March 2016 00:03:38 UTC+5:30, Jason Moore wrote:
>>
>> I don't understand this behavior:
>>
>> Python 3.5.1 |Continuum Analytics, Inc.| (default, Dec  7 2015, 11:16:01)
>> Type "copyright", "credits" or "license" for more information.
>>
>> IPython 4.1.2 -- An enhanced Interactive Python.
>> ?         -> Introduction and overview of IPython's features.
>> %quickref -> Quick reference.
>> help      -> Python's own help system.
>> object?   -> Details about 'object', use 'object??' for extra details.
>>
>> In [1]: from sympy import *
>>
>> In [2]: phi = symbols('phi', cls=Function)
>>
>> In [3]: t = symbols('t')
>>
>> In [4]: phi(t).xreplace({t: 0})
>> Out[4]: phi(0)
>>
>> In [5]: phi(t).xreplace({t: 0.0})
>> Out[5]: 1.61803398874989
>>
>> In [6]: phi(t).xreplace({t: 5.0})
>>
>> ---------------------------------------------------------------------------
>> KeyError                                  Traceback (most recent call
>> last)
>>
>> /home/moorepants/miniconda3/lib/python3.5/site-packages/sympy/core/evalf.py
>> in evalf(x, prec, options)
>>    1209     try:
>> -> 1210         rf = evalf_table[x.func]
>>    1211         r = rf(x, prec, options)
>>
>> KeyError: phi
>>
>> During handling of the above exception, another exception occurred:
>>
>> TypeError                                 Traceback (most recent call
>> last)
>> <ipython-input-6-ec5c48b4cb2f> in <module>()
>> ----> 1 phi(t).xreplace({t: 5.0})
>>
>>
>> /home/moorepants/miniconda3/lib/python3.5/site-packages/sympy/core/basic.py
>> in xreplace(self, rule)
>>    1086             args = tuple(args)
>>    1087             if not _aresame(args, self.args):
>> -> 1088                 return self.func(*args)
>>    1089         return self
>>    1090
>>
>>
>> /home/moorepants/miniconda3/lib/python3.5/site-packages/sympy/core/function.py
>> in __new__(cls, *args, **options)
>>     683     def __new__(cls, *args, **options):
>>     684         args = list(map(sympify, args))
>> --> 685         obj = super(AppliedUndef, cls).__new__(cls, *args,
>> **options)
>>     686         return obj
>>     687
>>
>>
>> /home/moorepants/miniconda3/lib/python3.5/site-packages/sympy/core/function.py
>> in __new__(cls, *args, **options)
>>     380         pr2 = min(cls._should_evalf(a) for a in result.args)
>>     381         if pr2 > 0:
>> --> 382             return result.evalf(mlib.libmpf.prec_to_dps(pr))
>>     383         return result
>>     384
>>
>>
>> /home/moorepants/miniconda3/lib/python3.5/site-packages/sympy/core/evalf.py
>> in evalf(self, n, subs, maxn, chop, strict, quad, verbose)
>>    1315             options['quad'] = quad
>>    1316         try:
>> -> 1317             result = evalf(self, prec + 4, options)
>>    1318         except NotImplementedError:
>>    1319             # Fall back to the ordinary evalf
>>
>>
>> /home/moorepants/miniconda3/lib/python3.5/site-packages/sympy/core/evalf.py
>> in evalf(x, prec, options)
>>    1215             if 'subs' in options:
>>    1216                 x = x.subs(evalf_subs(prec, options['subs']))
>> -> 1217             re, im = x._eval_evalf(prec).as_real_imag()
>>    1218             if re.has(re_) or im.has(im_):
>>    1219                 raise NotImplementedError
>>
>>
>> /home/moorepants/miniconda3/lib/python3.5/site-packages/sympy/core/function.py
>> in _eval_evalf(self, prec)
>>     484
>>     485         with mpmath.workprec(prec):
>> --> 486             v = func(*args)
>>     487
>>     488         return Expr._from_mpmath(v, prec)
>>
>>
>> /home/moorepants/miniconda3/lib/python3.5/site-packages/sympy/mpmath/ctx_mp_python.py
>> in __call__(self, prec, dps, rounding)
>>     344         if not rounding: rounding = rounding2
>>     345         if dps: prec = dps_to_prec(dps)
>> --> 346         return self.context.make_mpf(self.func(prec, rounding))
>>     347
>>     348     @property
>>
>>
>> /home/moorepants/miniconda3/lib/python3.5/site-packages/sympy/mpmath/libmp/libelefun.py
>> in f(prec, rnd)
>>     114     def f(prec, rnd=round_fast):
>>     115         wp = prec + 20
>> --> 116         v = fixed(wp)
>>     117         if rnd in (round_up, round_ceiling):
>>     118             v += 1
>>
>>
>> /home/moorepants/miniconda3/lib/python3.5/site-packages/sympy/mpmath/libmp/libelefun.py
>> in g(prec, **kwargs)
>>      95         memo_prec = f.memo_prec
>>      96         if prec <= memo_prec:
>> ---> 97             return f.memo_val >> (memo_prec-prec)
>>      98         newprec = int(prec*1.05+10)
>>      99         f.memo_val = f(newprec, **kwargs)
>>
>> TypeError: unsupported operand type(s) for >>: 'int' and 'mpf'
>>
>> Can someone explain to me what is going on? I would expect "t" to be
>> simply replaced with the number.
>>
>> Jason
>> moorepants.info
>> +01 530-601-9791
>
> --
> You received this message because you are subscribed to the Google Groups
> "sympy" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to [email protected].
> To post to this group, send email to [email protected].
> Visit this group at https://groups.google.com/group/sympy.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/sympy/b40c4bb2-e74a-4399-8a40-879e380ea65e%40googlegroups.com.
>
> For more options, visit https://groups.google.com/d/optout.

-- 
You received this message because you are subscribed to the Google Groups 
"sympy" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To post to this group, send email to [email protected].
Visit this group at https://groups.google.com/group/sympy.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/sympy/CAKgW%3D6J93TOhZxUL2D-qq55v%3D6_GgfWK6e38rx66gtq%2BHazTQw%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to