Function lct_gday 

pub fn lct_gday(
    lct_hours: f64,
    lct_minutes: f64,
    lct_seconds: f64,
    daylight_saving: i32,
    zone_correction: i32,
    local_day: f64,
    local_month: u32,
    local_year: u32,
) -> f64

Determine Greenwich Day for Local Time.

Original macro name: LctGDay