function plot_calibration_data(fname)
% plot_calibration_data  Plot raw calibration data for the thermistor

% -- Supply a default file name
if nargin<1, fname='thermistor_data.txt';  end

% -- Load the data and compute summary statistics for each column
D = load(fname);
T = D(1,:);         %  Temperature values in first row
V = D(2:end,:);     %  Voltage data in columns from second row until end
Vave = mean(V);     %  Mean of data in each column

% -- Plot the averaged reading versus the calibration temperature
plot(T,Vave,'o');
xlabel('Temperature (C)');   ylabel('Analog reading (10-bit scale)');
