CODEWITHSUNDEEP
pythonarrays
lte__
lte__

Reputation: 7586

for loop misery

I'm trying to loop through an array, compute some values and store them in another array (output). However, what I tried (see bellow) always prints the last value in the inarray and the last computed sum (not the max value, as intended) and the output array also only contains the last value. I figured the output.append(sum) should append the sum value each time throughout the loop, but it doesn't. If I print the sum values directly though, it shows on the console. What am I doing wrong?

def discountCombinations(inarray):
    for i in range(len(inarray)):
        max = 0
        maxi = 0
        output = list()
        ...
        #do stuff
        ...
        sum = new_y.sum()
        output.append(sum)
        print sum
        if sum > max:
            max = copy.copy(sum)
            maxi = copy.copy(i)
    print (max,": ", inarray[maxi])
    print output

Upvotes: 0

Views: 57

Answers (3)

Mohammed Q. Hussain
Mohammed Q. Hussain

Reputation: 46

In each iteration you are re-initializing the variable "output" as an empty list in this line: "output = list()". You just need to move this line before "for" loop.

Upvotes: 1

jarmod
jarmod

Reputation: 78842

You're resetting max, maxi, and output for every input item you process. You should only do this once, before processing any input items, for example:

max = 0
maxi = 0
output = list()

for i in range(len(inarray)):
    ...
    #do stuff
    ...

Upvotes: 3

Moses Koledoye
Moses Koledoye

Reputation: 78564

output = list() is defined in the for loop, so the result of the previous append is destroyed at the next iteration of the loop. Your max and maxi values are equally defined in the loop, and the same thing follows.

Upvotes: 5

Related Questions