How to declare variable for a function with other variable?

asked 2015-12-19 12:16:58 +0200

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n=var("n")
def T(n):
    a=1
    b=x
    if n==0:
        return a
    if n==1:
        return b
    else:
        for i in [2..n]:
            b=2*x*b-a
            a=(a+b)/(2*x)
    return b

Could you help me to compute T(i) at x=1 or anything ?Mean that I want to declare x is a variable of T(i), but I can't. Thank you so much

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answered 2015-12-19 20:03:57 +0200

vdelecroix
7397 ●19 ●81 ●164 http://www.labri.fr/pe...

As far as I understand this is what you want

def T(n):
    x = polygen(ZZ)     # or alternatively x = var("x")
    a=1
    b=x
    if n==0:
        return a
    if n==1:
        return b
    else:
        for i in [2..n]:
            b=2*x*b-a
            a=(a+b)/(2*x)
    return b

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Asked: 2015-12-19 12:16:58 +0200

Seen: 659 times

Last updated: Dec 19 '15

How to declare variable for a function with other variable? edit

1 Answer