Issue 1154: Don't do any calculation at import time
http://code.google.com/p/sympy/issues/detail?id=1154
New issue report by ondrej.certik:
This is bad, because it slows down "import sympy" and also makes debugging
difficult, as sympy is not yet fully loaded, mainly printing doesn't work
in Mul.flatten because of that.
The following patch "fixes" that. So we need to figure out some way to do
the same thing, but not at import time, but only when it's actually needed.
diff --git a/sympy/functions/special/polynomials.py
b/sympy/functions/special/polynomials.py
index eda626c..e595fa2 100644
--- a/sympy/functions/special/polynomials.py
+++ b/sympy/functions/special/polynomials.py
@@ -83,7 +83,7 @@ class chebyshevt(PolynomialSequence):
Chebyshev polynomial of the first kind, T_n(x)
"""
@staticmethod
- @recurrence_memo([S.One, _x])
+ [EMAIL PROTECTED]([S.One, _x])
def calc(n, prev):
return (2*_x*prev[n-1] - prev[n-2]).expand()
@@ -107,7 +107,7 @@ class chebyshevu(PolynomialSequence):
(-1) + 4*x**2
"""
@staticmethod
- @recurrence_memo([S.One, 2*_x])
+ [EMAIL PROTECTED]([S.One, 2*_x])
def calc(n, prev):
return (2*_x*prev[n-1] - prev[n-2]).expand()
@@ -184,7 +184,7 @@ class legendre(PolynomialSequence):
* http://en.wikipedia.org/wiki/Legendre_polynomial
"""
@staticmethod
- @recurrence_memo([S.One, _x])
+ [EMAIL PROTECTED]([S.One, _x])
def calc(n, prev):
return (((2*n-1)*_x*prev[n-1] - (n-1)*prev[n-2])/n).expand()
@@ -277,6 +277,6 @@ class hermite(PolynomialSequence):
* http://mathworld.wolfram.com/HermitePolynomial.html
"""
@staticmethod
- @recurrence_memo([S.One, 2*_x])
+ [EMAIL PROTECTED]([S.One, 2*_x])
def calc(n, prev):
return (2*_x*prev[n-1]-2*(n-1)*prev[n-2]).expand()
Issue attributes:
Status: Accepted
Owner: ----
Labels: Type-Defect Priority-Medium
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