Extract the number within the bracket

I have string a = 'a_b_c_d(1.0)'

I need to extract the number within the bracket.

my answer shoud be b = '1.0'

how can i do this using regular expression or other method?

Thank you

[Brian Hannan]

How about this?

regexp(x,'(?<=\().*(?=\))','match')

[Gopalakrishnan venkatesan]

Thank you

[Guillaume]

It may be safer to use a non-greedy * (that is *?) in case there is more than one bracketed expression in the string.

[Brian Hannan]

Good idea.

Answer 1

[Guillaume]

Any number of regular expression would do 'extract whatever is between two brackets:

str = 'a_b_c_d(1.0)';
regexp(str, '(?<=\()[^)]*(?=\))', 'match', 'once')

is one possibility. This

• looks ahead for an opening bracket.
• matches any number of characters as long as they're not a closing bracket
• looks behind for a closing bracket.

[Gopalakrishnan venkatesan]

Thank you

Answer 2

[Thorsten]

This extracts all digits and all '.' from a:

 numstr = a(regexp(a, '[\d\.]'))

This extracts all numbers between ( ), where number must have at least one digit before the point and one digit after the point:

 numstr = regexp(a, '\((\d+\.\d+)\)', 'tokens')

The outer \( and \) match the '(' and ')', resp., in a, and the inner ( ) are meta-characters to group a token.

[Gopalakrishnan venkatesan]

Thank you