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instance method

Float#nan?

() -> bool

nan? → true or false

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

    return RBOOL(isnan(value));
}

Returns true if self is a NaN, false otherwise.

Example

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

See also #modulo #negative? #magnitude #next_float also in 4.0 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0