This script shows how to load and plot fnirs data (.nirs format)

load_and_plot_nirs.R

# install the package if not available with:
# install.packages("R.matlab")
library(R.matlab)

# load the nirs file
data <- readMat("Simple_Probe.nirs")

# get the available names
names(data)

# format description:
# http://www.nmr.mgh.harvard.edu/martinos/software/homer/HOMER2_UsersGuide_121129.pdf#4

# find the dimensions of data: samples and channels
dim(data$d)

# number of channels
ncol(data$d)

# create a custom plotting function
myPlot <- function(y){
  plot(data$t, y,
       type = "l",
       xlab = "Time", ylab = "Intensity",
       ylim = c(range(data$d)),
       main = paste("Channel ", toString(y)))
  # add the lines when triggers occur
  lines(data$t, data$s*1500, # multiply the trigger value to make it visible
        type = "l", xlab = "Time", col = "red")
}

# apply the plotting function to all channels
apply(data$d[, 1:ncol(data$d)], 2, myPlot)

sessionInfo()