Louis Cypher's profile - activity

I don't know why this is happening, but here are some workarounds: one option is to replace

self._value(theta_1=item[0],mu_t=item[1],mu_j=item[1])

by

self._value(theta_1=item[0],mu_t=item[1],mu_j=item[1], e=e, pi=pi)

A second option: right after the line

self._value=self._value(**self.th1_dict)(**self.pre10_dict)(**self.constants).trig_reduce().simplify() #set dictionary values

add the line

self._value = self._value(**self.constants)

By the way, you can also replace the "constants" dictionary with

    self.constants={
        "pi": pi,
        "e": e
        }

to give better precision.

Thanks a million time for this indeed helpfull answer. BTW: that behaviour seems like a bug to me. After adding e=e... in the first of the if loops all the others also work fine. Looks like sage forgets about the constants. Should I try to file a bug here?

The Worksheet now is public at http://www.sagenb.org/home/pub/3912. The calculations failing are in the cell containing ###### 7 ######## and the following cell. Sorry for the dirty hacks in there and thanks in advance ;-)

The big question that remains to me is how to do that after miles of symbolic calculations. I tried using a dictionary and that failes. Copy paste is not a too good solution also since the argument I posted is (by far) the shortest. In that case I'd prefer to copy paste it completely to python, because my calculations are to slow and memory consuming anyway. Second I do not get what the difference of RR(-1/exp(1/10*abs(-0.0555555555556*(pi) - 26714619/51021164)) + 1) and -1/RR(e)^(1/10*abs(-0.0555555555556*RR(pi) - 26714619/51021164)) + 1 should be.

OK, thanks. This : http://ask.sagemath.org/question/1014/pi-and-e-not-evaluated-when-i-use-my-own-classes might be a related problem. There are also some sage constants that are not evaluated at all.

The problem seems to be related to what is imported. Another version where the object calculating the values are created earlier works fine. I imported matplotlib as plt and numpy as np so no modules of these should be conflicting, right?

This question might be related to this question: http://ask.sagemath.org/question/966/...

I have a symbolic calculation and I do evaluate it numerically. Within one of my classes (within my notebook; no external files) I evaluate this term

-1/e^(1/10*abs(-0.0555555555556*pi - 26714619/51021164)) + 1

within a for loop.

I am getting the following error:

File "", line 1, in <module> File "/tmp/tmpkItECC/___code___.py", line 113, in <module> __temp=MuObject.calcValue((mu_enlacement[i])(**param_dict)) File "/tmp/tmpJuxeqk/___code___.py", line 97, in calcValue self._result[self._k,_sage_const_0 ]=R(self._value(theta_1=item[_sage_const_0 ],mu_t=item[_sage_const_1 ],mu_j=item[_sage_const_1 ])) File "parent.pyx", line 988, in sage.structure.parent.Parent.__call__ (sage/structure/parent.c:7326) File "coerce_maps.pyx", line 156, in sage.structure.coerce_maps.NamedConvertMap._call_ (sage/structure/coerce_maps.c:4235)
File "expression.pyx", line 862, in sage.symbolic.expression.Expression._mpfr_ (sage/symbolic/expression.cpp:5117)
File "expression.pyx", line 796, in sage.symbolic.expression.Expression._eval_self (sage/symbolic/expression.cpp:4912) TypeError: Cannot evaluate symbolic expression to a numeric value.

If I copy paste the expression

print
(-1/e^(1/10*abs(-0.0555555555556*pi - 26714619/51021164)) + 1).n()

to my notebook it evaluates fine to:

0.0674319647572598

I even tried to replace pi and e using a dictionary but I can't get it working.

Any ideas what i am doing wrong?

Thanks in advance,

Markus P.S.: I can make the notebook public if usefull

Thanks for the answers. Would you mind explaining me what a SD 35.5. fodder ist?

I have an urgent problem with the sign function. I have done a symbolic calculation and want to evaluate the result numerically. The symbolic terms have a sgn() function within, which gives me an error when I try to evaluate the expression numerically. Please find the error below. I do not have the slightest ideas why sage can not evaluate that (simple) expression:

sign(1050*cos(61075634/181449129) + 900).n()

How can i solve that problem?

Thanks a lot in advance,

Best Markus

Error:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "_sage_input_60.py", line 10, in <module>
    exec compile(u'open("___code___.py","w").write("# -*- coding: utf-8 -*-\\n" + .....

execfile(os.path.abspath("___code___.py"))
  File "", line 1, in <module>

  File "/tmp/tmp4W3s9l/___code___.py", line 4, in <module>
    exec compile(u'qwer.n()
  File "", line 1, in <module>

  File "expression.pyx", line 4053, in sage.symbolic.expression.Expression._numerical_approx (sage/symbolic/expression.cpp:17894)
TypeError: cannot evaluate symbolic expression numerically

edit by kcrisman: Here's a minimal example:

sage: M = sgn(cos(3/2))
sage: M.n()

It doesn't suffice to do sgn(cos(1)), because that turns out to be 1.