calc_hour_angle: Calculate hour angle as in...

In USGS-R/streamMetabolizer: Models for Estimating Aquatic Photosynthesis and Respiration

Calculate hour angle as in http://education.gsfc.nasa.gov/experimental/July61999siteupdate/inv99Project.Site/Pages/solar.insolation.html.

Description

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)))
## Not run: 
library(ggplot2)
ggplot(hourdf, aes(x=hour, y=hragl)) +
  geom_hline(yintercept=0, color="gold") + geom_line()

## End(Not run)

USGS-R/streamMetabolizer documentation built on Aug. 15, 2023, 7:50 a.m.