Regular Expressions 101

Pro

^start of line

0*the literal 0 (48₁₀ / 60₈ / 30₁₆) , repeated any number of times

Group 1([1-9][0-9]*)?

?repeats the group contents below at most once:

Character Class[1-9]

1-9one character from 1 (49₁₀) to 9 (57₁₀)

Character Class[0-9]*

*matches any number of characters from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

Group 2(\.[0-9]*[1-9])?

?repeats the group contents below at most once:

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Character Class[0-9]*

*matches any number of characters from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

Character Class[1-9]

1-9one character from 1 (49₁₀) to 9 (57₁₀)

0*the literal 0 (48₁₀ / 60₈ / 30₁₆) , repeated any number of times

$end of line

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

25 tokens

^0*([1-9][0-9]*)?(\.[0-9]*[1-9])?0*$

New

$1$2