[Tutor] Re: Print record x in a file

[Kent Johnson]

David Holland wrote:
Kent,
I know that you know far more about python than me but
is that right ?
I created file with 4 records and this code did print
them all randomly:-
import random
i = 0
while i < 10:
    file = open('filename')
    listcontents = file.readlines()
    file.close()
    lenoflist = len(listcontents)-1
    x = random.randrange(0,lenoflist)
    print listcontents[x], i
    i = i +1
While although this code below does work many times
nothing is printed out.
import random
i = 0
while i < 10:
    file = open('test.rantxt')
    listcontents = file.readlines()
    file.close()
    lenoflist = len(listcontents)#-1
    x = random.randrange(0,lenoflist)
    print listcontents[x], i
    i = i +1
It sounds like your file has a blank line at the end. What do you get if you print 
len(listcontents)? Is it 4 or 5? Where do you think 'nothing' is coming from?

Try this:
import random
listcontents = [1,2,3,4]
for i in range(10):
    lenoflist = len(listcontents)-1
    x = random.randrange(0,lenoflist)
    print listcontents[x]
I never get a 4...
Kent
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