How to read numbers into variables from string

Question

I have strings that look like this:

user@pc: $ example="bla bla bla (m=100, number of steps=1.05)"

How can I read the values 100 and 1.05 into two variables that I can use them afterwards?

user@pc: $ echo $A
100
user@pc: $ echo $B
1.05

Add integers as strings to a variable bash, In BASH convert a string with . in float, How to do integer & float calculations, in bash, Argument string to integer in bash on Unix & Linux Stack Exchange, etc. — jww
– jww, Commented Dec 30, 2017 at 18:42

iBug · Accepted Answer · 2017-12-30 14:13:35Z

1

Use an extra tool like grep to extract numbers first:

NUMS=($(grep -Eo '[0-9]+(\.[0-9]+)?' <<<"${example}"))
A=${NUMS[0]}
B=${NUMS[1]}

answered Dec 30, 2017 at 14:13

iBug

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Comments

ctac_ · Accepted Answer · 2017-12-30 17:09:19Z

0

Another way with bash

example="bla bla bla (m=100, number of steps=1.05)"
var=(${example//[^0-9 \.]})
for i in ${var[@]};do
  echo $i
done

answered Dec 30, 2017 at 17:09

ctac_

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Not quite effective in certain cases: example="123aaa456bbb789