How to extract integer or float from string

Question

I have got dosage strength values like 20.5 mg,20 mg in string . I want to extract only integer or float value.

Below is what I have tried so far

def parseint(self,string):
   return int(''.join([x for x in string if x.isdigit()]))

But this is not working in all cases.

ex1)

parseint('2 mg')
o/p- 2

ex2)

parseint('10.2 mg')
o/p - 102

Expected output:

i/p "20.5 MG" o/p- 20.5
i/p "20.0 MG" o/p - 20.0
i/p "20.0 MG" o/p - 20.0

20.5 and 10.2 also aren't integers, your title says floats as well but your question states only integers, which is correct? — Sayse, Oct 11 '18 at 06:18
`' . '` is not a digit. yes that is why it is not coming with integer. how can i have that too. — Rahul Rajpoot, Oct 11 '18 at 06:19

score 2 · Answer 1 · answered Oct 11 '18 at 06:26

2

Using Regex.

Ex:

import re


def parseint(string):
    m = re.search(r"(\d*\.?\d*)", string)
    return m.group() if m else None

s1 = "20.5 mg,"
s2 = "20 mg"

print(parseint(s1))
print(parseint(s2))

Output:

20.5
20

answered Oct 11 '18 at 06:26

Rakesh

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score 0 · Answer 2 · answered Oct 11 '18 at 06:19

0

def parseint(string):
    return float(''.join([x for x in string if x.isdigit() or x == '.']))

Something like this should work.

answered Oct 11 '18 at 06:19

Ninad Gaikwad

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Actually this is working but in one case where values like "25 MG" . it is giving me output like 25.0, but i think i need 25 only . – Rahul Rajpoot Oct 11 '18 at 06:24

vash_the_stampede · Answer 3 · 2018-10-11T06:30:43.160

0

Using list comprehension, with .split(),float, andint`

res = [float(i.split()[0]) if '.' in i else int(i.split()[0]) for i in lst]

Expanded explanation

lst = ['2 mg', '10.2 mg', '20.5 MG']
for i in lst:
    if '.' in i:
        print(float(i.split()[0]))
    else:
        print(int(i.split()[0]))
# 2
# 10.2
# 20.5

edited Oct 11 '18 at 06:30

answered Oct 11 '18 at 06:24

vash_the_stampede

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How to extract integer or float from string

3 Answers3