R/filter_vpts.R
filter_vpts.Rd
Time and night/day selection in a time series of vertical profiles ('vpts')
filter_vpts(x, min, max, nearest, night, elev = -0.268, offset = 0)
x | A |
---|---|
min | Minimum datetime to be included. POSIXct value or character string convertable to POSIXct. |
max | Maximum datetime to be included. POSIXct value or character string convertable to POSIXct. |
nearest | If specified, |
night | When TRUE select only night time profiles, when FALSE select only day time profiles, as classified by check_night. |
elev | numeric. Sun elevation in degrees defining night time. May also be a numeric vector of length two, with first element giving sunset elevation, and second element sunrise elevation. |
offset | numeric. Time duration in seconds by which to shift the start and end of night time. May also be a numeric vector of length two, with first element added to moment of sunset and second element added to moment of sunrise. See check_night for details. |
An object of class 'vpts', or an object of class 'vp'
if argument nearest
is specified.
Returns profiles for which min <= timestamp profile < max. Selection for night and day occurs by check_night.
#> Irregular time series of vertical profiles (class vpts) #> #> radar: KBGM #> # profiles: 1934 #> time range (UTC): 2016-09-01 00:02:00 - 2016-09-10 11:56:00 #> time step (s): min: 180 max: 16320# select profiles later than 02-Sep-2016 filter_vpts(example_vpts, min = "2016-09-02")#> Irregular time series of vertical profiles (class vpts) #> #> radar: KBGM #> # profiles: 1651 #> time range (UTC): 2016-09-02 00:06:00 - 2016-09-10 11:56:00 #> time step (s): min: 180 max: 16320# select the profile nearest to 2016-09-01 03:00 UTC: filter_vpts(example_vpts, nearest = "2016-09-01 03:00")#> Vertical profile (class vp) #> #> radar: KBGM #> source: #> nominal time: 2016-09-01 03:02:00 #> generated by:# select profiles between than 1 and 3 UTC on 02-Sep-2016: filter_vpts(example_vpts, min = "2016-09-02 01:00", max = "2016-09-02 03:00")#> Irregular time series of vertical profiles (class vpts) #> #> radar: KBGM #> # profiles: 13 #> time range (UTC): 2016-09-02 01:04:00 - 2016-09-02 02:59:00 #> time step (s): min: 540 max: 600# select day time profiles (day time periods from sunrise to sunset) filter_vpts(example_vpts, night=FALSE)#> Irregular time series of vertical profiles (class vpts) #> #> radar: KBGM #> # profiles: 910 #> time range (UTC): 2016-09-01 10:35:00 - 2016-09-10 11:56:00 #> time step (s): min: 180 max: 41460# select night time profiles, with nights starting starting and ending at civil twilight # (when the sun is 6 degrees below the horizon): filter_vpts(example_vpts, night=TRUE, elev = -6)#> Irregular time series of vertical profiles (class vpts) #> #> radar: KBGM #> # profiles: 938 #> time range (UTC): 2016-09-01 00:10:00 - 2016-09-10 10:10:00 #> time step (s): min: 180 max: 55200# select night time profiles from 3 hours after sunset to 2 hours before sunrise filter_vpts(example_vpts, night=TRUE, offset=c(3,-2)*3600)#> Irregular time series of vertical profiles (class vpts) #> #> radar: KBGM #> # profiles: 578 #> time range (UTC): 2016-09-01 02:39:00 - 2016-09-10 08:41:00 #> time step (s): min: 180 max: 65460