crossing_zero_up: Zero crossing of a periodical function

In Susarro/arqastwb: Archaeoastronomy algorithms

Description

Zero crossing of a periodical function

Usage

crossing_zero_up(fnc, from, to, period, search_interval = 0.005,
  incrx = 0.01, silent = FALSE, trace = TRUE)

Arguments

fnc	Function
from	Initial value of the interval to be searched
to	Final value of the interval to be searched
period	Period of the function
search_interval	Search interval for each root
incrx	increment in x to calculate the derivative used to check the slope in the point of crossing
silent	If true a text progress bar is shown
trace	If true prints a trace

Value

vector of roots of the function

Examples

fnc<-function(x) apparent_equatorial_position(x,"sun")$declination
from <- str2jd("2014-03-08")
to <- str2jd("2018-03-08")
crossing_zero_up(fnc,from,to,period=365.25,search_interval=10)

Susarro/arqastwb documentation built on May 21, 2019, 10:28 a.m.