finding and printing index in a loop

[pavlos03]

hi again,

can't seem to figure out a way to print a nested lists index while iterating through it.

for example lets say i have a list group that has nested lists of points

Python Code:

for i in group:
    for j in i:
        print "index no." + str(i) + str(j)

the str(i) will give me the complete items inside the nested list 'i', but not the index number, meaning whether 'j' is in 'i' position of 0, 1, 2 or even the 'j' position inside 'i' etc. If i want to check the script usually i use print commands in order to understand where the mistake is or where the script crashes.

I've tried many ways, but I don't know how to print the index no. and for sure a counter is not a sophisticated way !

any help appreciated.

Pav

[Mitch]

Hi,

You could use the Python built-in function 'Enumerate'. Enumerate will iterate over a sequence and return each element and its index.

Python Code:

#create list (just a simple example)
group=[]
for i in range (5):
    group.append([i,i,i])
 
#now enumerate the list
for (n,element) in enumerate(group):
    print "Element index "+str(n)+" is: ",element

For each index in the list, you get a tuple composed of (index, element)
HTH, --Mitch

[pavlos03]

thanks Mitch,


that's all i need

Pav