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instance method

Float#nan?

float.nan? → true or false

static VALUE
flo_is_nan_p(VALUE num)
{
    double value = RFLOAT_VALUE(num);

    return isnan(value) ? Qtrue : Qfalse;
}

Returns true if float is an invalid IEEE floating point number.

Example

a = -1.0      #=> -1.0
a.nan?        #=> false
a = 0.0/0.0   #=> NaN
a.nan?        #=> true

See also #modulo #negative? #magnitude #next_float also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2 · 3.1