Update Documentation for cos_solar_zenith_angle Function

modules/data.atmosphere/R/solar_angle.R

@@ -1,14 +1,25 @@
-#' Cosine of solar zenith angle
+#' Cosine of Solar Zenith Angle
+#'
+#' Calculates the cosine of the solar zenith angle based on the given parameters. 
+#' This angle is crucial in determining the amount of solar radiation reaching a point on Earth.
 #'
 #' For explanations of formulae, see https://web.archive.org/web/20180307133425/http://www.itacanet.org/the-sun-as-a-source-of-energy/part-3-calculating-solar-angles/
 #'
 #' @author Alexey Shiklomanov
-#' @param doy Day of year
-#' @param lat Latitude
-#' @param lon Longitude
-#' @param dt Timestep
-#' @param hr Hours timestep
-#' @return `numeric(1)` of cosine of solar zenith angle
+#' @param doy Day of year. Integer representing the day of the year (1-365).
+#' @param lat Latitude in degrees. Positive for the Northern Hemisphere and negative for the Southern Hemisphere.
+#' @param lon Longitude in degrees. Positive for East and negative for West.
+#' @param dt Time interval in seconds. Represents the duration over which the measurement is averaged or integrated.
+#' @param hr Hour of the day (0-23). Specifies the specific hour for which the calculation is made.
+#'
+#' @return Numeric value representing the cosine of the solar zenith angle.
+#'
+#' @references 
+#' "Understanding Solar Position and Solar Radiation" - RAMMB: [Link](https://rammb.cira.colostate.edu/wmovl/vrl/tutorials/euromet/courses/english/nwp/n5720/n5720005.htm)
+#'
+#' @examples
+#' cos_solar_zenith_angle(doy = 150, lat = 45, lon = -93, dt = 3600, hr = 12)
+#'
 #' @export
 cos_solar_zenith_angle <- function(doy, lat, lon, dt, hr) {
     et <- equation_of_time(doy)