tican (version 1.1.0)

ttpeak: Return time to peak from time-intensity data

Description

This function returns the time to peak from time-intensity curve data. Raw data is smoothed using a loess smoother, and the time of peak is returned. Time to a specified proportion of the peak (e.g. time to 90% of peak) can be calculated. It is recommended that plotresult is set to TRUE in the first instance to visually confirm the analysis.

Usage

ttpeak(
  data,
  timevar,
  intensityvar,
  loess.span = 0.1,
  peakproportion = NULL,
  plotresult = FALSE,
  ...
)

Value

The time at which the loess curve is at its peak. Depending on the plotresult argument can also return a plot of the smoothed curve.

Arguments

data

A dataframe with time and intensity values as columns.

timevar

A character string (in quotes) with the dataframe column name for the time variable.

intensityvar

A character string (in quotes) with dataframe column name for the intensity variable.

loess.span

A number between 0 and 1, with larger values resulting in a smoother curve.

peakproportion

A number between 0 and 1 which is used in the time to peak proportion calculations. If a number is entered the function will return the time to peak proportion.

plotresult

TRUE or FALSE to determine whether a plot of the results is generated.

...

Additional arguments to be passed into the loess() function.

Examples

# Example usage: Please see package vignettes on CRAN