ch_hydrograph_plot {CSHShydRology}

Hydrograph plot

Description

Creates a hydrograph plot for simulated, observed, and inflow hydrograph series, including precipitation if provided. The secondary y axis will be used to plot the precip time series.

Usage

ch_hydrograph_plot(
  flows = NULL,
  precip = NULL,
  prd = NULL,
  winter_shading = FALSE,
  winter_colour = "cyan",
  range_mult_flow = NULL,
  range_mult_precip = 1.5,
  flow_labels = NULL,
  ylabel = NULL,
  precip_label = "Precipitation [mm]",
  leg_pos = NULL,
  leg_box = NULL,
  zero_axis = TRUE
)

Arguments

flows

data frame of flows to plot

precip

data frame of precipitation values to plot

prd

period to use in plotting

winter_shading

optionally adds a transparent cyan shading for the December 1st to March 31st period in each year that is plotted. Default is FALSE.

winter_colour

colour to use in winter shading polygons

range_mult_flow

range multiplier for max value in hydrograph. This is useful in preventing overlap if precip is also plotted. This value should not be less than 1.0, otherwise the values will be cutoff in the plot.

range_mult_precip

range multiplier for max value in precipitation plot (default 1.5)

flow_labels

string vector of labels for flow values

ylabel

text label for y-axis of the plot (default 'Flow [m^3/s]')

precip_label

text label for precipitation y-axis (default 'Precipitation [mm]')

leg_pos

string specifying legend placement on plot e.g. topleft, right, etc., and is consistent with the legend function options. If NULL, the function will place the legend left, if precip added, on the topleft otherwise).

leg_box

boolean on whether to put legend in an opaque white box or not. If NULL (the default), the function will automatically not use a white box and leave the background of the legend transparent.

zero_axis

fixes the y axis to start exactly at zero (default TRUE). By default, R will plot the values with a small buffer for presentation. Be warned that if this option is set to TRUE, the minimum value is set to zero without checking if any flow values are less than zero. This option should not be used for reservoir stage plotting, since most reservoir stage is typically reported as an elevation.

Details

Assumes that the supplied time series have the same length and duration in time. If this is not true, then the defined period or period calculated from the first available flow series will be used to determine the plotting limits in time. The supplied time series should be in xts format. Note that a plot title is purposely omitted in order to allow the automatic generation of plot titles.

Value

Returns TRUE if the function is executed properly.

Author(s)

Robert Chlumsky

Examples

# example with synthetic random data
dd <- seq.Date(as.Date("2010-10-01"), as.Date("2013-09-30"),by = 1)
x <- abs(rnorm(length(dd)))
y <- abs(rnorm(length(dd))) * x
df <- data.frame("Date" = dd, x, y)
myprd <- "2011-10-01/2012-09-30"

precip <- data.frame("Date" = dd," precip" = abs(rnorm(length(dd))) * 10)

# basic hydrograph plot
ch_hydrograph_plot(flows = df, winter_shading = FALSE)

# with different labels and winter shading
ch_hydrograph_plot(flows = df, winter_shading = TRUE,
 flow_labels = c("simulated", "observed"))

# add precipitation, increase the plot ranges to separate flows and precip, and add a legend box
ch_hydrograph_plot(flows = df, precip = precip, range_mult_flow = 1.7, 
range_mult_precip = 2, leg_box = TRUE)