Returns exp(x) / 2 for x >= log(maxFloat(T)).
pub fn expo2(x: anytype) @TypeOf(x)
pub fn expo2(x: anytype) @TypeOf(x) {
const T = @TypeOf(x);
return switch (T) {
f32 => expo2f(x),
f64 => expo2d(x),
else => @compileError("expo2 not implemented for " ++ @typeName(T)),
};
}