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Draw a load duration curve

Source: R/draw_ldc.R
draw_ldc.Rd

Creates a load duration curve visualization from the outputs of calc_ldc and summ_ldc as a ggplot object.

Usage

draw_ldc(
  .tbl_calc,
  .tbl_summ,
  y_lab = NULL,
  ldc_legend_name = "Allowable Load at State Water Quality Standard",
  measurement_name = "Measurement Value",
  measurement_shape = 21,
  measurement_color = "dodgerblue",
  measurement_alpha = 1,
  summary_name = "Summarized Measured Load",
  summary_stat_shape = 12,
  summary_stat_color = "red",
  label_nudge_y = 0,
  label_font_family = "Arial",
  label_font_size = 3,
  label_break = TRUE
)

Arguments

.tbl_calc

data frame object created by calc_ldc

.tbl_summ

data frame object created by summ_ldc

y_lab

optional string for y-axis label name, will be appended with units automatically. default is NULL.

ldc_legend_name

string, provides the name used for the allowable pollutant load line in the legend. required.

measurement_name

string, provides the name used for measured load values in the legend. required.

measurement_shape

aesthetic value passed to the layer plotting measured load values. defaults to 21.

measurement_color

aesthetic value passed to the layer plotting measured load values. defaults to "dodgerblue".

measurement_alpha

aesthetic value passed to the layer plotting measured load values. defaults to 1.

summary_name

string, provides the name used for summary statistic values in the legend. required.

summary_stat_shape

aesthetic value passed to the layer plotting summary statistic values. defaults to 12.

summary_stat_color

aesthetic value passed to the layer plotting summary statistic values. defaults to "red".

label_nudge_y

numeric value to vertically nudge flow category labels. If a log10 transformed scale is being used, a log value is probably appropriate for example log10(1000).

label_font_family

string specifying font family to use in flow category labels.

label_font_size

numeric value specifying font size to use in flow category labels.

label_break

logical, add line breaks to flow category labels. Labels will break at spaces.

Value

ggplot object

Examples

# Basic example using built in Tres Palacios data
library(dplyr)
library(units)
library(ggplot2)
# Format data
install_unit("cfu")
df <- as_tibble(tres_palacios) %>%
        ## filter data so this run quicker
        filter(!is.na(Indicator_Bacteria)) %>%
        ## flow must have units, here is is in cfs
        mutate(Flow = set_units(Flow, "ft^3/s")) %>%
        ## pollutant concentration must have units
        mutate(Indicator_Bacteria = set_units(Indicator_Bacteria, "cfu/100mL"))
# Calculate LDC

## specify the allowable concentration
allowable_concentration <- 126
## set the units
units(allowable_concentration) <- "cfu/100mL"
df_ldc <- calc_ldc(df,
                   Q = Flow,
                   C = Indicator_Bacteria,
                   allowable_concentration = allowable_concentration)

# Summarize LDC
df_sum <- summ_ldc(df_ldc,
                   Q = Flow,
                   C = Indicator_Bacteria,
                   Exceedance = P_Exceedance,
                   groups = Flow_Category,
                   method = "geomean")

# Create ggplot object
draw_ldc(df_ldc,
         df_sum,
         y_lab = expression(paste(italic("E. coli"))),
         label_nudge_y = log10(1000)) +
         scale_y_log10() +
         theme(legend.title = element_blank(),
               legend.direction = "vertical",
               legend.position = "bottom")


## cleanup
remove_unit("cfu")