O'Reilly logo

Programming PHP, 3rd Edition by Peter MacIntyre, Kevin Tatroe, Rasmus Lerdorf

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Name

is_nan

Synopsis

bool is_nan(float value)

Returns true if value is a “not a number” value, or false if value is a number.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required