Displaying an axis scale in mm rather than pixels

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I have written a code for image analysis that uses the number of pixels throughout to calculate lengths. Now I want to plot graphs and have my axis reading in millimetres rather than number of pixels. I have a calibration factor calculated, is there a simple way I can have axis in millimetres. I need this code to work for multiple pictures therefore using the xticks and xticklabels method would help.

Accepted Answer

Looky
Looky on 1 Nov 2017
Edited: Looky on 1 Nov 2017
It's a bit tricky without any example data, but this should do the trick.
conversion=0.1; % in mm/pixel
addMM=@(x) sprintf('%.3fmm',x*conversion);
xticklabels(cellfun(addMM,num2cell(xticks'),'UniformOutput',false));
yticklabels(cellfun(addMM,num2cell(yticks'),'UniformOutput',false));
You can fine tune how many digits are displayed by editing the '%.3fmm' in the second line(see formatSpec). Change the variable conversion to your needs. It's in mm per pixel. Hope that helps, if not, just ask. Note that Matlab still treats the axis in Pixel, but displays the converted mm. If you make changes to xtick and ytick, you have to call the above lines again.
  2 Comments
Robbie McDermott
Robbie McDermott on 2 Nov 2017
That is fantastic, does exactly what I wanted it to! Thank you, saved me two week work!
Stelios Fanourakis
Stelios Fanourakis on 9 Jan 2019
It is a very nice solution, indeed. Thanks a lot as well. I'd like to ask whether there is a way to have more steps, like every 50 mm or every 10 mm, instead of almost a 100 mm

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More Answers (2)

elvis okacha
elvis okacha on 10 Apr 2019
Look I'm trying to implement your solution within a button program in my guitar,but I still get error that 'undefined variable 'xticks''.allitle new to Matias.is there some additional code on the use of stick and xticklabels?kindly
  9 Comments
Walter Roberson
Walter Roberson on 12 Apr 2019
set() the axes XTickLabels and YTickLabels properties instead of calling xticklabels() and yticklabels()

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elvis okacha
elvis okacha on 10 Apr 2019
Sorry.'looky' not 'look'

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