Python Write To File Missing Lines

Question

I'm having trouble using python to write strings into a file: (what I'm trying to do is using python to generate some C programs) The code I have is the following:

filename = "test.txt"
i = 0
string = "image"
tempstr = ""
average1 = "average"
average2 = "average*average"
output = ""
FILE = open(filename,"w")
while i < 20:
    j = 0
    output = "square_sum = square_sum + "
    while j < 20:        
        tempstr = string + "_" + str(i) + "_" + str(j)        
        output = output + tempstr + "*" + tempstr + " + " + average2 + " - 2*" + average1 + "*" + tempstr        
        if j != 19:        
            output = output + " + "
        if j == 19:
            output = output + ";"        
        j = j + 1
    output = output + "\n"
    i = i + 1
    print(output)
    FILE.writelines(output)    
FILE.close

The print gives me correct output, but the FILE has last line missing and some of the second last line missing. What's the problem in writing strings into file?

Thank you!

Answer 1

Probably help if you called the method...

FILE.close()

Answer 2

The problem is that you aren't calling the close() method, just mentioning it in the last line. You need parens to invoke a function.

Python's with statement can make that unnecessary though:

with open(filename,"w") as the_file:
    while i < 20:
        j = 0
        output = "square_sum = square_sum + "
        ...
        print(output)
        the_file.writelines(output)

When the with clause is exited, the_file will be closed automatically.