You can probably write your own parser and go through each line until you stumble upon the 'x' and 'y' parameters. Collect the data in a vector and then proceed to plot the 'x' and 'y' values.
A sample line parser for the txt file.
file = fopen('mctan.txt');
line = fgetl(file);
for i=1:6
if any(line == 'x values')
disp("x values need to be stored")
elseif any(line == 'y values')
disp("y values need to be stored")
line = fgetl(file);
end
fclose(file);
