View source: R/calc_monthly_cumulative_stats.R
calc_monthly_cumulative_stats  R Documentation 
Calculate cumulative monthly flow statistics for each month of the year of daily flow values from a daily streamflow
data set. Calculates statistics from all values from complete years, unless specified. Defaults to volumetric cumulative flows,
can use use_yield
and basin_area
to convert to areabased water yield. Returns a tibble with statistics.
calc_monthly_cumulative_stats(
data,
dates = Date,
values = Value,
groups = STATION_NUMBER,
station_number,
percentiles = c(5, 25, 75, 95),
use_yield = FALSE,
basin_area,
water_year_start = 1,
start_year,
end_year,
exclude_years,
months = 1:12,
transpose = FALSE
)
data 
Data frame of daily data that contains columns of dates, flow values, and (optional) groups (e.g. station numbers).
Leave blank or set to 
dates 
Name of column in 
values 
Name of column in 
groups 
Name of column in 
station_number 
Character string vector of seven digit Water Survey of Canada station numbers (e.g. 
percentiles 
Numeric vector of percentiles to calculate. Set to 
use_yield 
Logical value indicating whether to calculate areabased water yield, in mm, instead of volumetric discharge.
Default 
basin_area 
Upstream drainage basin area, in square kilometres, to apply to observations. Three options: (1) Leave blank if (2) A single numeric value to apply to all observations. (3) List each basin area for each group/station in groups (can override HYDAT value if listed) as such 
water_year_start 
Numeric value indicating the month ( 
start_year 
Numeric value of the first year to consider for analysis. Leave blank or set well before start date (i.e.

end_year 
Numeric value of the last year to consider for analysis. Leave blank or set well after end date (i.e.

exclude_years 
Numeric vector of years to exclude from analysis. Leave blank or set to 
months 
Numeric vector of months to include in analysis. For example, 
transpose 
Logical value indicating whether to transpose rows and columns of results. Default 
A tibble data frame with the following columns, default units in cubic metres, or millimetres if use_yield and basin_area provided:
Month 
month (MMMDD) of cumulative statistics 
Mean 
monthly mean of all cumulative flows for a given month of the year 
Median 
monthly mean of all cumulative flows for a given month of the year 
Maximum 
monthly mean of all cumulative flows for a given month of the year 
Minimum 
monthly mean of all cumulative flows for a given month of the year 
P'n' 
each monthly nth percentile selected of all cumulative flows for a given month of the year 
Default percentile columns:
P5 
monthly 5th percentile of all cumulative flows for a given month of the year 
P25 
monthly 25th percentile of all cumulative flows for a given month of the year 
P75 
monthly 75th percentile of all cumulative flows for a given month of the year 
P95 
monthly 95th percentile of all cumulative flows for a given month of the year 
Transposing data creates a column of "Statistics" and subsequent columns for each year selected.
# Run if HYDAT database has been downloaded (using tidyhydat::download_hydat())
if (file.exists(tidyhydat::hy_downloaded_db())) {
# Calculate annual monthly cumulative volume statistics
calc_monthly_cumulative_stats(station_number = "08NM116")
# Calculate annual monthly cumulative volume statistics with default HYDAT basin area
calc_monthly_cumulative_stats(station_number = "08NM116",
use_yield = TRUE)
# Calculate annual monthly cumulative volume statistics with custom basin area
calc_monthly_cumulative_stats(station_number = "08NM116",
use_yield = TRUE,
basin_area = 800)
}
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.