How to write this algorithm in a python code?

Question

I have the following code.

for k in range( ( N + 1 ) * K ):
 if k >= 0 and k <= K-1:
 # do something
 # n = 0
 elif k >= K and k <= 2*K-1:
 # do something
 # n = 1
 elif k >= 2*K and k <= 3*K-1:
 # do something
 # n = 2
 ...
 ...

The 'do something' is complicated to explain but I replaced it with the affectation n = p.

How can I write this explicitly?

More specifically, if k is in the set {p*K,...,(p+1)*K-1} for p = 0 to N, then do something. How can I do it in a code?

• Paul Hankin: Are you looking for a way to compute n from k? n = k//K

Answer 1

You could just have three loops, no?

for k in range(K):
 # do something
for k in range(K, 2*K-1):
 # do something
for k in range(2*K-1, (N+1)*K):
 # do the rest

• 1-approximation: In fact, I have 'N' loops, one for each range(n*K,(n+1)*K).
• user2357112: @1-approximation: Then you're going to have to clarify what # do something is, and how the various # do somethings differ from each other.

Answer 2

for loop_id in xrange(N):
 for i in xrange(K):
 k = K * loop_id + i
 do_smth(loop_id, i, k)

• 1-approximation: Thanks. If I want to keep the loop in range(K*(N+1)), can I still do it?
• Eugene Primako: If range [0, K*(N+1)] is ok for you, you can just change range limits (from my piece of code) to N+2 and K+1 accordingly. If you do not want to have number K*(N+1) in the range - probably some hack (i.e. handling this case separately) will be required.