| Title: | Seasonal Mid-Summer Drought Characteristics |
| Version: | 0.1.1 |
| Description: | Characterization of a mid-summer drought (MSD) with precipitation based statistics. The MSD is a phenomenon of decreased rainfall during a typical rainy season. It is a feature of rainfall in much of Central America and is also found in other locations, typically those with a Mediterranean climate. Details on the metrics are in Maurer et al. (2022) <doi:10.5194/hess-26-1425-2022>. |
| URL: | https://github.com/EdM44/msdrought/, https://edm44.github.io/msdrought/ |
| BugReports: | https://github.com/EdM44/msdrought/issues |
| Depends: | R (≥ 3.6.0) |
| License: | MIT + file LICENSE |
| Encoding: | UTF-8 |
| LazyData: | true |
| Imports: | ggplot2, lubridate, quantmod, signal, stats, xts |
| Suggests: | dplyr, knitr, rmarkdown, stringr, terra, tidyr, tools, zoo |
| RoxygenNote: | 7.3.2 |
| VignetteBuilder: | knitr |
| NeedsCompilation: | no |
| Packaged: | 2025-03-08 01:46:22 UTC; EMaurer |
| Author: | Turner Uyeda [aut], Ed Maurer [aut, cre, cph], Iris Stewart-Frey [aut], Kenneth Joseph [aut], Alex Avila [aut] |
| Maintainer: | Ed Maurer <emaurer@scu.edu> |
| Repository: | CRAN |
| Date/Publication: | 2025-03-08 03:10:01 UTC |
Change behavior of which.max to work as if it had an na.rm=TRUE option
Description
Change behavior of which.max to work as if it had an na.rm=TRUE option using https://gis.stackexchange.com/questions/392666/app-function-returns-a-wrong-output-format answer recommended by R Hijmans.
Usage
f.which.max(i)
Arguments
i |
A vector |
Examples
## Not run:
f.which.max(1:5)
f.which.max(NA)
## End(Not run)
Finding indices for Dates Relevant to the MSD Calculations
Description
This function pulls the indices associated with the dates that correspond with the Mid Summer Drought, as well as the indices that indicate first and last day of each year. This function is used in conjunction with the MSD function.
Usage
msdDates(x, peakwindow1, minwindow1, minwindow2, peakwindow2)
Arguments
x |
Date vector |
peakwindow1 |
desired date in MMDD format to begin search for early peak |
minwindow1 |
desired date in MMDD format to begin search for minimum |
minwindow2 |
desired date in MMDD format to end search for minimum |
peakwindow2 |
desired date in MMDD format to end search for late peak |
Value
Vector containing the indices corresponding to each year's beginning date, end date, and the critical MSD dates
Examples
x <- seq(from = as.Date("1981-01-01"), to = as.Date("1985-12-31"), by = "day")
output <- msdDates(x, peakwindow1 = "05-01", minwindow1 = "06-01",
minwindow2 = "08-31", peakwindow2 = "10-31")
msdFilter – A triangular Filter for smoothing data
Description
The filter will take a weighted average of a specified number of points around the point of interest to create a smoother time series. For example, if the size of the filter is set to 31, the filter will take the 15 points before and after the point of interest (for a total of 31 points), and calculate a weighted average based on how far away the points are from the point of interest.
Usage
msdFilter(x, window = 31, quantity = 2)
Arguments
x |
TimeSeries or numeric vector |
window |
Size of Filter [Default = 31] |
quantity |
Number of passes to apply filter [Default = 2] |
Value
Vector of Yearly data
Examples
dates <- seq(from = as.Date("1981-01-01"), to = as.Date("1982-12-31"), by = "day")
ts <- xts::xts(runif(length(dates), 0, 50),dates)
filteredData <- msdrought::msdFilter(ts, window = 31, quantity = 2)
Mid Summer Drought Time Series Graphs
Description
Plots the Time Series of Mid Summer Drought data. The input must be in the form of daily data, with the first data point being January 1st of a respective year.
Usage
msdGraph(x, year, peakwindow1, minwindow1,
minwindow2, peakwindow2, quantity,
window, timeVector)
Arguments
x |
vector of data or xts |
year |
year of interest |
peakwindow1 |
date in MMDD format to begin analysis (window 1) |
minwindow1 |
date in MMDD format to end analysis (window 1) |
minwindow2 |
date in MMDD format to begin analysis (window 2) |
peakwindow2 |
date in MMDD format to end analysis (window 2) |
quantity |
number of times the filter is to be run |
window |
size of filter |
timeVector |
vector of dates (not needed for xts inputs) |
Value
Graph of Time Series Data
Examples
## Not run:
data("timeseries")
ts <- timeseries
msdrought::msdGraph(ts, 1982)
## End(Not run)
Mid Summer Drought Function
Description
Generates all relevant statistics for the Mid Summer Drought by running the msdStats function for every applicable metric. The output of msdMain is a dataframe containing every msdStats output for the available years of data.
Usage
msdMain(x, peakwindow1, minwindow1,
minwindow2, peakwindow2, quantity,
window, timeVector)
Arguments
x |
xts or vector of data |
peakwindow1 |
desired date in MMDD format to begin analysis (window 1) |
minwindow1 |
desired date in MMDD format to end analysis (window 1) |
minwindow2 |
desired date in MMDD format to begin analysis (window 2) |
peakwindow2 |
desired date in MMDD format to end analysis (window 2) |
quantity |
amount of times the filter is run |
window |
size of filter |
timeVector |
vector of dates (not needed for xts inputs) |
Value
Data frame of all relevant MSD Statistics
Examples
data("timeseries")
ts <- timeseries
df <- msdrought::msdMain(ts)
Main Mid Summer Drought Calculation Function
Description
This function calculates the different statistics of the mid summer drought from a Time Series. The input must be in the form of daily data, with the first data point being January 1st of a respective year.
Usage
msdStats(x, dates, fcn)
Arguments
x |
Filtered xts data (from msdFilter) |
dates |
Vector of Dates (from the msdDates function) |
fcn |
Specify what values to be pulled from the function. Options are 'duration', 'intensity', 'firstMaxValue', 'secondMaxValue', 'min', 'mindex'. |
Value
SpatRaster or TimeSeries of Yearly data
Examples
data("timeseries")
ts <- timeseries
dates <- zoo::index(ts)
filteredData <- msdrought::msdFilter(ts, window = 31, quantity = 2)
keyDates <- msdDates(dates)
msdrought::msdStats(filteredData, keyDates, fcn = "duration")
msdrought package included timeseries data
Description
A subset of data from the UCSB CHIRPS data set
Usage
timeseries
Format
## 'timeseries' An xts object with precipitation data over a series of five years:
- Date
date in YYYY-MM-DD format
- Precipitation
daily precipitation in millimeters (mm)
...
Source
<https://www.chc.ucsb.edu/data/chirps>