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Create a Psychrometric Chart

Source: R/graph_psychrometric.R
graph_psychrometric.Rd

This function generates a psychrometric chart based on input temperature and relative humidity data.

Usage

graph_psychrometric(
  mydata,
  Temp = "Temp",
  RH = "RH",
  data_col = NULL,
  data_alpha = 0.5,
  LowT = 16,
  HighT = 25,
  LowRH = 40,
  HighRH = 60,
  Temp_range = c(0, 40),
  y_func = "calcMR",
  ...
)

Arguments

mydata

A data frame containing temperature and relative humidity data.

Temp

Column name in mydata for temperature values.

RH

Column name in mydata for relative humidity values.

data_col

Name of column to use for colouring points. Default is "Sensor" if present, otherwise "RH".

data_alpha

Value to supply for make points more or less transparent. Default is 0.5.

LowT

Numeric value for lower temperature limit of the target range. Default is 16°C.

HighT

Numeric value for upper temperature limit of the target range. Default is 25°C.

LowRH

Numeric value for lower relative humidity limit of the target range. Default is 40%.

HighRH

Numeric value for upper relative humidity limit of the target range. Default is 60%.

Temp_range

Numeric vector of length 2 specifying the overall temperature range for the chart. Default is c(0, 40).

y_func

Function to calculate y-axis values. See above for options, default is mixing ratio (`calcMR`).

...

Additional arguments passed to y_func.

Value

A ggplot object representing the psychrometric chart.

Details

Humidity and conservation functions can be used for the y-axis.

  • calcHR: Humidity Ratio (g/kg)

  • calcMR: Mixing Ratio (g/kg)

  • calcAH: Absolute Humidity (g/m^3)

  • calcSH: Specific Humidity (g/kg)

  • calcAD: Air Density (kg/m^3)

  • calcDP: Dew Point (°C)

  • calcFP: Frost Point (°C)

  • calcEnthalpy: Enthalpy (kJ/kg)

  • calcPws: Saturation vapor pressure (hPa)

  • calcPw: Water Vapour Pressure (hPa)

  • calcPI: Preservation Index

  • calcLM: Lifetime

  • calcEMC_wood: Equilibrium Moisture Content (wood)

Examples


# mydata file
filepath <- data_file_path("mydata.xlsx")
mydata <- readxl::read_excel(filepath, sheet = "mydata", n_max = 100)

# Basic usage with default settings
graph_psychrometric(mydata, Temp, RH)


# Custom temperature and humidity ranges
graph_psychrometric(mydata, Temp, RH, LowT = 8, HighT = 28, LowRH = 30, HighRH = 70)


# Using a different psychrometric function (e.g., Absolute Humidity)
graph_psychrometric(mydata, Temp, RH, y_func = calcAH)


# Adjusting the overall temperature range of the chart
graph_psychrometric(mydata, Temp, RH, Temp_range = c(12, 30))