My name is Elijus Slamas and I am a 2nd year University of Lethbridge student working under Dr. Julie Lee-Yaw. I have been studying geometric morphometrics for a little while which lead me to sliding landmarks. I have been using tpsDig and tpsUtil to set up landmarks for my project, however I encountered an issue while using the "Make Sliders File" function in tpsUtil. When I create a .NTS file my parameters do not add up (the .NTS file is attached to this question). The parameter specifying how many specimens I have is 15 while I only have 5 specimens. I am also confused on what the variable parameter that is 3 entails. The original .NTS file also did not contain dimensions and that is something I added myself. What could be some of the problems that or mistakes that I am making in creating the .NTS file?
I had a look at your file... I think you are interpreting the first .NTS file line as you interpret when you are dealing with coordinates, which is not the case (more or less). When you are dealing with coordinates you have:
1 N C M DIM = 3
where,
1 is for the type of matrix (rectangular)
N is the number of specimens
C is the number of coordinates.
M is the number of missing data (usually zero)
It is best if you think of this first line as the components of your matrix, instead of what is usually means in a coordinates file.
Like this:
1 R C M
where,
R = number of rows in the matrix (in your case this is actually the number of semilandmarks, which is 15, but if you are thinking of a coordinates file, this would be translated as the number of specimens - here is the confusion you've made)
C = as the number of columns in your file (in your case, you have 3 columns)
So if we interpret the first line of your semilandmarks file - aside from the matrix line, which is:
1 15 3
it would mean that semilandmark 15 should be sliding between landmarks (or semilandmarks) 1 and 3 and in the direction of 1 to 3.
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