Regular Expressions 101

^start of line

.*?any character (except for line terminators), repeated any number of times

Non-Capturing Group(?:([-+]?[0-9]*\.?[0-9]+(?:[eE][-+]?[0-9]+)?).*|$)

1st Alternative([-+]?[0-9]*\.?[0-9]+(?:[eE][-+]?[0-9]+)?).*

Group 1([-+]?[0-9]*\.?[0-9]+(?:[eE][-+]?[0-9]+)?)

Character Class[-+]?

?matches at most one character from the set below:

-the literal - (45₁₀ / 55₈ / 2D₁₆)

+the literal + (43₁₀ / 53₈ / 2B₁₆)

Character Class[0-9]*

*matches any number of characters from the set below:

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

\.?optionally matches the literal . (46₁₀ / 56₈ / 2E₁₆)

Character Class[0-9]+

+matches at least one character from the set below:

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

Non-Capturing Group(?:[eE][-+]?[0-9]+)?

?repeats the group contents below at most once:

Character Class[eE]

ethe literal e (101₁₀ / 145₈ / 65₁₆) (case sensitive)

Ethe literal E (69₁₀ / 105₈ / 45₁₆) (case sensitive)

Character Class[-+]?

?matches at most one character from the set below:

-the literal - (45₁₀ / 55₈ / 2D₁₆)

+the literal + (43₁₀ / 53₈ / 2B₁₆)

Character Class[0-9]+

+matches at least one character from the set below:

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

.*any character (except for line terminators), repeated any number of times

2nd Alternative$

$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.

Search reference

Regular Expression

^.*?(?:([-+]?[0-9]*\.?[0-9]+(?:[eE][-+]?[0-9]+)?).*|$)

New

.&.
0.0119885482338&.&.
.&2.25880593895
.&.&.&.&.&.&.&.
.&0.295142083575&.
0.708323350364
.&.&0.193766679861
.&.&.&.&7.65239874523E-4&.&.