Regular Expressions 101

Positive Lookbehind(?<=(?<!\b.|\d)\.)

Negative Lookbehind(?<!\b.|\d)

1st Alternative\b.

\ban ASCII word boundary

.any character (except for line terminators)

2nd Alternative\d

\da digit

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

\s+any whitespace character, repeated at least once

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

(?<=(?<!\b.|\d)\.)\s+

New

At 12.51 p.m. local time, J. Knapp, former U.S. Navy,  went out for a walk. Yes he did. And then a Mw6.3 earthquake happened.