Converting Numpy array into list prints out extra zeros? Python

Question

I made an array using numpy, and need to convert each value into a string list.

This is the solution I found that worked :

props = np.arange(0.2,0.5,0.1)
props = [str(i) for i in props]

However when I print it out this is the result:

Out[177]: ['0.2', '0.30000000000000004', '0.4000000000000001']]

The result I want is ['0.2', '0.3', '0.4'].

What am I doing wrong?

Is there a more efficient way of doing this or is this a convulated way?

Does this answer your question? [How to pretty-print a numpy.array without scientific notation and with given precision?](https://stackoverflow.com/questions/2891790/how-to-pretty-print-a-numpy-array-without-scientific-notation-and-with-given-pre) — pasbi, Mar 23 '20 at 14:36
haha I can't help but laugh that this a question asked by many other programming newbs. Cheers guys! — apang, Mar 23 '20 at 14:44
@apang maybe you can consider accepting the answer that you found useful so that this question can be closed — Junkrat, Mar 23 '20 at 14:50
yep, I was trying to accept your answer below but was prompted to wait 4 minutes before doing so. — apang, Mar 23 '20 at 15:02

score 1 · Accepted Answer · answered Mar 23 '20 at 14:38

1

You can use np.around:

import numpy as np

props = np.arange(0.2,0.5,0.1)
props = np.around(props, 1)
props = [str(i) for i in props]

#output
['0.2', '0.3', '0.4']

Or:

props = np.arange(0.2,0.5,0.1)
props = [str(np.around(i, 1)) for i in props]

answered Mar 23 '20 at 14:38

Junkrat

score 0 · Answer 2 · answered Mar 23 '20 at 14:46

0

Just round them up

props = np.arange(0.2,0.5,0.1)
props = [str(round(i,2)) for i in props]

['0.2', '0.3', '0.4']

answered Mar 23 '20 at 14:46

Shahir Ansari

score 0 · Answer 3 · answered Mar 23 '20 at 14:58

0

Beside the round()- function you can just use use this little workaround:

import numpy as np
props = np.arange(0.2,0.5,0.1)
props = [str(int(i*10)/10) for i in props]
print(props)

answered Mar 23 '20 at 14:58

tifi90

3 Answers3