sollong_date: Calculation of date corresponding to given value of solar...
In MetFns: Analysis of Visual Meteor Data

Description Usage Arguments Details Value Note Author(s) See Also Examples

Calculates calendar date and time corresponding to specified value of solar longitude (J2000.0) and specified year.

1	sollong_date(solval,year,date1=NULL,date2=NULL)

`solval`	numeric vector of length one specifying solar longitude.
`year`	numeric vector of length one specifying year.
`date1`	character vector of length one specifying start date, given in `"%Y-%m-%d %H:%M:%S"` format (UTC timezone).
`date2`	character vector of length one specifying end date, given in `"%Y-%m-%d %H:%M:%S"` format (UTC timezone).

The function sollong_date calculates date corresponding to the given value of solar longitude, for specified year between 1984 and 2030. It searches for a solution in a interval bounded by date1 and date2. If user does not specify date1 and date2, they are, by default, equal to the 1st od January and the 31st of December, respectively.

sollong_date returns object of POSIXct class, calendar date in "%Y-%m-%d %H:%M:%S" format (UTC timezone).

Arguments date1 and date2 should belong to the same year.

Kristina Veljkovic

date_sollong

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## calculate date corresponding to 1 degree of solar longitude 
## search between dates 1 and 31 March 2017
sollong_date(1,year=2017,"2017-03-01","2017-03-31")

Loading required package: astroFns
Loading required package: lubridate

Attaching package: 'lubridate'

The following object is masked from 'package:base':

    date

Loading required package: plotrix
Loading required package: pracma

Attaching package: 'MetFns'

The following object is masked from 'package:stats':

    filter

[1] "2017-03-21 16:15:33 UTC"