pub fn sqrtf(mut d: f32) -> f32 {
    let mut q = 1.;

    d = if d < 0. { f32::NAN } else { d };

    if d < 5.293_955_920_339_377_e-23 {
        d *= 1.888_946_593_147_858_e+22;
        q = 7.275_957_614_183_426_e-12;
    }

    if d > 1.844_674_407_370_955_2_e+19 {
        d *= 5.421_010_862_427_522_e-20;
        q = 4_294_967_296.;
    }

    // http://en.wikipedia.org/wiki/Fast_inverse_square_root
    let mut x = f32::from_bits(0x_5f37_5a86 - ((d + 1e-45).to_bits() >> 1));

    x *= 1.5 - 0.5 * d * x * x;
    x *= 1.5 - 0.5 * d * x * x;
    x *= 1.5 - 0.5 * d * x * x;
    x *= 1.5 - 0.5 * d * x * x;

    if d == f32::INFINITY {
        f32::INFINITY
    } else {
        (x * d * q)
    }
}
/// Square root function
///
/// The error bound of the returned value is 3.5 ULP.
Square root function
The error bound of the returned value is 3.5 ULP.
Square root function The error bound of the returned value is 3 . 5 ULP .
pub fn sqrtf(mut d: f32) -> f32 {
    let mut q = 1.;
    d = if d < 0. { f32::NAN } else { d };
    if d < 5.293_955_920_339_377_e-23 {
        d *= 1.888_946_593_147_858_e+22;
        q = 7.275_957_614_183_426_e-12;
    }
    if d > 1.844_674_407_370_955_2_e+19 {
        d *= 5.421_010_862_427_522_e-20;
        q = 4_294_967_296.;
    }
    // http://en.wikipedia.org/wiki/Fast_inverse_square_root
    let mut x = f32::from_bits(0x_5f37_5a86 - ((d + 1e-45).to_bits() >> 1));
    x *= 1.5 - 0.5 * d * x * x;
    x *= 1.5 - 0.5 * d * x * x;
    x *= 1.5 - 0.5 * d * x * x;
    x *= 1.5 - 0.5 * d * x * x;
    if d == f32::INFINITY {
        f32::INFINITY
    } else {
        (x * d * q)
    }
}
pub fn sqrtf ( mut d : f32 ) -> f32 { let mut q = 1. ; d = if d < 0. { f32 :: NAN } else { d } ; if d < 5.293_955_920_339_377_e-23 { d *= 1.888_946_593_147_858_e+22 ; q = 7.275_957_614_183_426_e-12 ; } if d > 1.844_674_407_370_955_2_e+19 { d *= 5.421_010_862_427_522_e-20 ; q = 4_294_967_296. ; } // http://en.wikipedia.org/wiki/Fast_inverse_square_root let mut x = f32 :: from_bits ( 0x_5f37_5a86 - ( ( d + 1e-45 ) . to_bits ( ) >> 1 ) ) ; x *= 1.5 - 0.5 * d * x * x ; x *= 1.5 - 0.5 * d * x * x ; x *= 1.5 - 0.5 * d * x * x ; x *= 1.5 - 0.5 * d * x * x ; if d == f32 :: INFINITY { f32 :: INFINITY } else { ( x * d * q ) } }
Square root function
The error bound of the returned value is 3.5 ULP.
Square root function The error bound of the returned value is 3 . 5 ULP .
d
f32
d
f32