transition_dates {phenocamr} | R Documentation |
Calculates transition dates for a PhenoCam time series
Description
Segments of a PhenoCam time series and calculates threshold based transition dates for all segments. This function is rarely called stand alone and 'phenophases()' should be preferred when evaluating PhenoCam time series.
Usage
transition_dates(
data,
lower_thresh = 0.1,
middle_thresh = 0.25,
upper_thresh = 0.5,
percentile = 90,
penalty = 0.5,
seg_length = 14,
reverse = FALSE,
plot = FALSE
)
Arguments
data |
a PhenoCam data file or data structure |
lower_thresh |
the minimum threshold used (default = 0.1) |
middle_thresh |
the middle threshold used (default = 0.25) |
upper_thresh |
the maximum threshold used (default = 0.5) |
percentile |
time series percentiles to process (mean, 50, 75, 90) |
penalty |
how sensitive is the algorithm, lower is more sensitve (< 1 ) |
seg_length |
minimum length of a segment to be evaluated |
reverse |
flip the direction of the processing |
plot |
plot for debugging purposes |
Value
Transition date estimates in UNIX time, including uncertainties and the threshold values estimated for each section of a time series.
Examples
## Not run:
# download demo data
download_phenocam(site = "harvard$",
veg_type = "DB",
roi_id = "1000",
frequency = "3")
# read the data and calculate transition dates
df <- read_phenocam(file.path(tempdir(),"harvard_DB_1000_3day.csv"))
my_dates <- transition_dates(df,
lower_thresh = 0.1,
middle_thresh = 0.25,
upper_thresh = 0.5,
percentile = 90,
reverse = FALSE,
plot = FALSE)
## End(Not run)
[Package phenocamr version 1.1.5 Index]