Calculate hour angle using the NASA solar insolation method. — calc_hour_angle • streamMetabolizer

This is an approximation when hour is in clock time; should actually be given in solar time

Usage

calc_hour_angle(hour, format = c("degrees", "radians"))

Arguments

hour: Numeric value or vector. hour since solar midnight as number between 0 and 23.999.
format: The format of both the input and the output. May be "degrees" or "radians".

Value

Numeric value or vector, in the units specified by format, indicating the angle corresponding to each value supplied in hour.

Examples

hourdf <- data.frame(hour=c(0:12,12.5:23.5),
  hragl=streamMetabolizer:::calc_hour_angle(c(0:12,12.5:23.5)))
library(ggplot2)
ggplot(hourdf, aes(x=hour, y=hragl)) +
  geom_hline(yintercept=0, color="gold") + geom_line()