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can't assign value to array element

Joe Heafner heafnerj at spam.vnet.net
Sun Nov 3 21:23:54 EST 2002 
Hi.
In my attempt to seriously learn Python (2.2.1 running on Mac OS X), I've 
been trying to code some simple numerical algorithms. Here is my code for 
one routine:

a=0.
b=1.4
y0=0.
m=10

h = (b-a)/m
t = zeros(m, Float)
t[0] = a
y = zeros(m, Float)
y[0] = b

for j in range(0,m,1):
    print j # for debugging purposes
    t = t[j]
    y = y[j]
    k1 = h*fprimexy(t,y)
    k2 = h*fprimexy(t+h/2., y+0.5*k1)
    k3 = h*fprimexy(t+h/2., y+0.5*k2)
    k4 = h*fprimexy(t+h, y+k3)
    y[j+1] = y+(k1+2.*k2+2.k3+k4)/6.
    t[j+1] = a+h*(j+1)

When run, this code give the error "TypeError: object does not support 
item assignment" for hte next to last line. I presume the last line would 
give the same error. I'm very new to Python and haven't been able to find 
documentation about htis specific problem, and I've been working 
(literally) all day on this. What am I doint wrong? I'd appreciate any 
help.

Thanks.
JH
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