Loop commands equivalent in IDL to python

Question

Just a quick question regarding converting loop commands in IDL to python.

I have the following loop structure in IDL syntax:

for ... do begin
   for ... do begin
      if ...
         ...
      endif else begin
         ....
      endelse
   endfor
endfor

Now, I would say that is roughly translates to

for ... :
   for ... :
      if ...
         ...
      end if else:
         ....
      endelse
   endfor
endfor

In python.

However, I would say the endelse and endfor commands are redundant? But what should I replace them with?

Answer 1

You are partially right, you just need to abandon the endelse and endfor and replace else if with elif.

for ... :
   for ... :
      if ...:
         ....
      elif:
         ....

From the Python documentation, here is an example for an If statement:

>>> x = int(raw_input("Please enter an integer: "))
Please enter an integer: 42
>>> if x < 0:
...     x = 0
...     print 'Negative changed to zero'
... elif x == 0:
...     print 'Zero'
... elif x == 1:
...     print 'Single'
... else:
...     print 'More'
...
More

For statement

>>> # Measure some strings:
... words = ['cat', 'window', 'defenestrate']
>>> for w in words:
...     print w, len(w)
...
cat 3
window 6
defenestrate 12