Factoring Polynomials
Scott David Daniels
Scott.Daniels at Acm.Org
Thu Dec 18 21:47:46 CET 2008
eric wrote:
> On Dec 18, 8:37 pm, collin.da... at gmail.com wrote:
>> ... I dont know how to implement the quadratic equation ...
>
> with numpy:
> from numpy import *
>
> s=[1,-1]
> x = -b+s*sqrt( b**2-4*a*c )/(2*a)
Numpy is pretty heavyweight for this.
For built in modules you have a few choices:
For real results:
from math import sqrt
For complex results:
from cmath import sqrt
or you can simply use:
(value) ** .5
Then you can do something like:
def quadsolve(a, b, c):
try:
discriminant = sqrt(b**2 - 4 * a * c)
except ValueError:
return () # No results at all.
if discriminant: # two results
return ((-b - discriminant) / (2 * a),
(-b + discriminant) / (2 * a))
else: # a single result (discriminant is zero)
return (-b / (2 * a),)
--Scott David Daniels
Scott.Daniels at Acm.Org
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