MATLAB: Griddata size and length mismatch error while they are the same length

errorinterpolationMATLAB

I have this matrix that I need to interpolate, so I'm using griddata for that.
Nonetheless it keep giving me the following error:
Error using griddata (line 110)
The lengths of X and Y must match the size of Z.
The thing is I've checked all it and my "X" (yys1) and "Y"(zzs1) should be the rigth lengths for "Z"(AAA). yys1 is a 57×1 double, zzs1 is a 99×1 double, while AAA is a 57×99 double. XIT and ZIT are a new grid to which the values need to be interpolated, these are 1001×2002 double.
See the code I typed in the workspace below and the error it gives, I would appreciate any and all help 😉
>> griddata(yys1,zzs1,AAA,XIT,ZIT,'natural');
Error using griddata (line 110)
The lengths of X and Y must match the size of Z.
 
>> griddata(yys1,zzs1',AAA,XIT,ZIT,'natural');
Error using griddata (line 110)
The lengths of X and Y must match the size of Z.
 
>> griddata(yys1',zzs1,AAA,XIT,ZIT,'natural');
Error using griddata (line 110)
The lengths of X and Y must match the size of Z.
 
>> griddata(yys1',zzs1',AAA,XIT,ZIT,'natural');
Error using griddata (line 110)
The lengths of X and Y must match the size of Z.
 
>> length(yys1)
ans =
    57
>> length(zzs1)
ans =
    99
>> size(AAA)
ans =
    57    99
Thus in otherwords I have no clue what I'm doing wrong, could someone please point out what mistake I'm making or why matlab is throwing this error?

Best Answer

"I have no clue what I'm doing wrong"
You've been caught by what I call matlab's split personality. Most functions in matlab use a row/column coordinate system but a few others use a X/Y coordinate system where X corresponds to columns and Y correspond to rows. griddata falls into the latter case and thus:
  • The length of X must match the number of columns in Z
  • The length of Y must match the number of rows in Z
In other words, you've got the lengths of your X and Y swapped!
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