Re: [Tutor] Advise...

[Jacob S.]

Thanks everyone!
Kent started the suggestion of making a code object, but everyone else seems 
to have worked their way to it.
Beautiful! I only have to call exec once, and it cuts down time 
considerably.

Here is the new code.
Jacob Schmidt
Please remind me if I've forgotten anything.
### Start ###################
from __future__ import division
from math import *
import psyco
psyco.full()
def reimannsum(fofx,x,max1):
   total = 0
   step = 1e-5
   exec "def f(x): return %s" % fofx
   while x <= max1:
       total = total+f(x)
       x = x+step
   return abs(total*step)
fofx = raw_input("What is the function? ")
minimum = raw_input("What is the minimum? ")
maximum = raw_input("What is the maximum? ")
minimum = float(minimum)
maximum = float(maximum)
print reimannsum(fofx,minimum,maximum)
#### End ##############################
If the user must be able to enter in the function, then it would be
better
to evaluate this once and turn it into some sort of function that
you can
call inside the loop (it's the eval that is so expensive).  How to
do that
depends a lot on how complex the possible functions can be (if
they'll only
include 'x*+/-' and numbers, for example, it's not so tricky).
exp = raw_input('Type expression')
func = eval('lambda x: " + exp)
print func(42)
etc...
Or if you really can't grokm lambda:
exec('def func(x): return " + exp)
should do the same...
Alan G.

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