Question

i = range(0,40,1)
y = 0.1 * cos((i)/20 * pi)

The error I get is this:

TypeError: unsupported operand type(s) for /: 'list' and 'int'`

I am not sure how to remove that error. I type-casted i to int, but its a list, thus can’t be type-casted. I am following this example. http://msenux.redwoods.edu/math/python/simple.php

Answer 1

They are using pylab’s arange, not simple python range. And this is the problem when importing *: you don’t know which method comes from where. Import just pylab and reference to all its methods/constants with pylab.. You will really love this way of programming when you’ve got several imports.

import pylab
i = pylab.arange(0, 40, 1) # or pylab.arange(40) will suffice
y = 0.1 * pylab.cos(i / 20. * pylab.pi)

will work.