Is there a numpy function that allows you to specify start, step, and number?

A deleted answer pointed out that linspace takes an endpoint parameter.

With that, 2 examples given in other answers can be written as:

In [955]: np.linspace(0, 0+(0.1*3),3,endpoint=False)
Out[955]: array([ 0. ,  0.1,  0.2])

In [956]: np.linspace(0, 0+(5*3),3,endpoint=False)
Out[956]: array([  0.,   5.,  10.])

In [957]: np.linspace(0, 0+(1.25*9),9,endpoint=False)
Out[957]: array([  0.  ,   1.25,   2.5 ,   3.75,   5.  ,   6.25,   7.5 ,   8.75,  10.  ])

Look at the functions defined in numpy.lib.index_tricks for other ideas on how to generate ranges and/or grids. For example, np.ogrid[0:10:9j] behaves like linspace.

def altspace(start, step, count, endpoint=False, **kwargs):
   stop = start+(step*count)
   return np.linspace(start, stop, count, endpoint=endpoint, **kwargs)

Some of the other solutions didn't work for me, so since I was already comfortable using np.linspace I decided to throw together a function that replaces linspace's num with a step argument.

def linspace(start, stop, step=1.):
  """
    Like np.linspace but uses step instead of num
    This is inclusive to stop, so if start=1, stop=3, step=0.5
    Output is: array([1., 1.5, 2., 2.5, 3.])
  """
  return np.linspace(start, stop, int((stop - start) / step + 1))

An example output:

linspace(9.5, 11.5, step=.5)
array([ 9.5, 10. , 10.5, 11. , 11.5])

Edit: I misread the question, the original question wanted a function that omitted the stop argument. I'll still leave this here, as I think it could be useful to some who stumble upon this question as it's the only one I've found that's similar to my original question of finding a function with start, stop, and step, rather than num

def by_num_ele(start,step,n_elements):
    return numpy.arange(start,start+step*n_elements,step)

maybe?

Thanks for that question. I had the same issue. The (from my perspective) shortest and most elegant way is:

import numpy as np
start=0
step=1.25
num=9

result=np.arange(0,num)*step+start

print(result)

returns

[  0.     1.25   2.5    3.75   5.     6.25   7.5    8.75  10.  ]