Plots means, medians, maximums, minimums, and percentiles for each day of the year of flow values from a daily streamflow data set. Can determine statistics of rolling mean days (e.g. 7-day flows) using the roll_days argument. Calculates statistics from all values, unless specified. The Maximum-Minimum band can be removed using the plot_extremes argument and the percentile bands can be customized using the inner_percentiles and outer_percentiles arguments. Data calculated using calc_daily_stats() function. Returns a list of plots.

plot_daily_stats(
  data,
  dates = Date,
  values = Value,
  groups = STATION_NUMBER,
  station_number,
  roll_days = 1,
  roll_align = "right",
  water_year_start = 1,
  start_year,
  end_year,
  exclude_years,
  complete_years = FALSE,
  months = 1:12,
  ignore_missing = FALSE,
  plot_extremes = TRUE,
  plot_inner_percentiles = TRUE,
  plot_outer_percentiles = TRUE,
  inner_percentiles = c(25, 75),
  outer_percentiles = c(5, 95),
  add_year,
  log_discharge = TRUE,
  log_ticks = ifelse(log_discharge, TRUE, FALSE),
  include_title = FALSE
)

Arguments

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 NULL if using station_number argument.

dates

Name of column in data that contains dates formatted YYYY-MM-DD. Only required if dates column name is not 'Date' (default). Leave blank or set to NULL if using station_number argument.

values

Name of column in data that contains numeric flow values, in units of cubic metres per second. Only required if values column name is not 'Value' (default). Leave blank if using station_number argument.

groups

Name of column in data that contains unique identifiers for different data sets, if applicable. Only required if groups column name is not 'STATION_NUMBER'. Function will automatically group by a column named 'STATION_NUMBER' if present. Remove the 'STATION_NUMBER' column beforehand to remove this grouping. Leave blank if using station_number argument.

station_number

Character string vector of seven digit Water Survey of Canada station numbers (e.g. "08NM116") of which to extract daily streamflow data from a HYDAT database. Requires tidyhydat package and a HYDAT database. Leave blank if using data argument.

roll_days

Numeric value of the number of days to apply a rolling mean. Default 1.

roll_align

Character string identifying the direction of the rolling mean from the specified date, either by the first ('left'), last ('right'), or middle ('center') day of the rolling n-day group of observations. Default 'right'.

water_year_start

Numeric value indicating the month (1 through 12) of the start of water year for analysis. Default 1.

start_year

Numeric value of the first year to consider for analysis. Leave blank or set well before start date (i.e. 1800) to use from the first year of the source data.

end_year

Numeric value of the last year to consider for analysis. Leave blank or set well after end date (i.e. 2100) to use up to the last year of the source data.

exclude_years

Numeric vector of years to exclude from analysis. Leave blank or set to NULL to include all years.

complete_years

Logical values indicating whether to include only years with complete data in analysis. Default FALSE.

months

Numeric vector of months to include in analysis. For example, 3 for March, 6:8 for Jun-Aug or c(10:12,1) for first four months (Oct-Jan) when water_year_start = 10 (Oct). Default summarizes all months (1:12).

ignore_missing

Logical value indicating whether dates with missing values should be included in the calculation. If TRUE then a statistic will be calculated regardless of missing dates. If FALSE then only those statistics from time periods with no missing dates will be returned. Default FALSE.

plot_extremes

Logical value to indicate plotting a ribbon with the range of daily minimum and maximum flows. Default TRUE.

plot_inner_percentiles

Logical value indicating whether to plot the inner percentiles ribbon. Default TRUE.

plot_outer_percentiles

Logical value indicating whether to plot the outer percentiles ribbon. Default TRUE.

inner_percentiles

Numeric vector of two percentile values indicating the lower and upper limits of the inner percentiles ribbon for plotting. Default c(25,75), set to NULL for no inner ribbon.

outer_percentiles

Numeric vector of two percentile values indicating the lower and upper limits of the outer percentiles ribbon for plotting. Default c(5,95), set to NULL for no outer ribbon.

add_year

Numeric value indicating a year of daily flows to add to the daily statistics plot. Leave blank or set to NULL for no years.

log_discharge

Logical value to indicate plotting the discharge axis (Y-axis) on a logarithmic scale. Default FALSE.

log_ticks

Logical value to indicate plotting logarithmic scale ticks when log_discharge = TRUE. Ticks will not appear when log_discharge = FALSE. Default to TRUE when log_discharge = TRUE.

include_title

Logical value to indicate adding the group/station number to the plot, if provided. Default FALSE.

Value

A list of ggplot2 objects with the following for each station provided:

Daily_Stats

a plot that contains daily flow statistics

Default plots on each object:

Mean

daily mean

Median

daily median

25-75 Percentiles

a ribbon showing the range of data between the daily 25th and 75th percentiles

5-95 Percentiles

a ribbon showing the range of data between the daily 5th and 95th percentiles

Minimum-Maximum

a ribbon showing the range of data between the daily minimum and maximums

'Year'

(on annual plots) the daily flows for the designated year

See also

Examples

# Run if HYDAT database has been downloaded (using tidyhydat::download_hydat())
if (file.exists(tidyhydat::hy_downloaded_db())) {

# Plot daily statistics using a data frame and data argument with defaults
flow_data <- tidyhydat::hy_daily_flows(station_number = "08NM116")
plot_daily_stats(data = flow_data,
                 start_year = 1980)
                  
# Plot daily statistics using only years with no missing data
plot_daily_stats(station_number = "08NM116",
                 complete_years = TRUE)
 
# Plot daily statistics and add a specific year's daily flows                
plot_daily_stats(station_number = "08NM116",
                 start_year = 1980,
                 add_year = 1985)                
                  
# Plot daily statistics for 7-day flows for July-September months only
plot_daily_stats(station_number = "08NM116",
                 start_year = 1980,
                 roll_days = 7,
                 months = 7:9)
                 
}
#> $Daily_Statistics

#>