Say I want to loop from 0 to 100 but with a step of 1/2. If you try
for i in range(0, 100, 0.5):
whatever
You have to use integer steps for range
() and xrange()
. That's why your 0.5 step gets internally converted to 0 and you get that error. Try for i in [j / 2.0 for j in xrange(100 * 2)]:
for x in map(lambda i: i * 0.5, range(0,200)):
#Do something with x
For large ranges it is better to use an generator expression than building a list explicitly:
for k in ( i*0.5 for i in range(200) ):
print k
This consumes not much extra memory, is fast und easy to read. See http://docs.python.org/tutorial/classes.html#generator-expressions
You'll have to either create the loop manually, or define your own custom range function. The built-in requires an integer step value.
Python2.x:
for idx in range(0, int(100 / 0.5)):
print 0.5 * idx
outputs:
0.0
0.5
1.0
1.5
..
99.0
99.5
Numpy:
numpy.arange would also do the trick.
numpy.arange(0, 100, 0.5)
If you have numpy
, here are two ways to do it:
numpy.arange(0, 100, 0.5)
numpy.linspace(0, 100, 200, endpoint=False)