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PADCAT - concatenate vectors with different lengths by padding with NaN
M = PADCAT(V1, V2, V3, ..., VN) concatenates the vectors V1 through VN
into one large matrix. All vectors should have the same orientation,
that is, they are all row or column vectors. The vectors do not need to
have the same lengths, and shorter vectors are padded with NaNs.
The size of M is determined by the length of the longest vector. For
row vectors, M will be a N-by-MaxL matrix and for column vectors, M
will be a MaxL-by-N matrix, where MaxL is the length of the longest
vector.
Examples:
a = 1:5 ; b = 1:3 ; c = [] ; d = 1:4 ;
padcat(a,b,c,d) % row vectors
% -> 1 2 3 4 5
% 1 2 3 NaN NaN
% NaN NaN NaN NaN NaN
% 1 2 3 4 NaN
CC = {d.' a.' c.' b.' d.'} ;
padcat(CC{:}) % column vectors
% 1 1 NaN 1 1
% 2 2 NaN 2 2
% 3 3 NaN 3 3
% 4 4 NaN NaN 4
% NaN 5 NaN NaN NaN
[M, TF] = PADCAT(..) will also return a logical matrix TF with the same
size as R having true values for those positions that originate from an
input vector. This may be useful if any of the vectors contain NaNs.
Example:
a = 1:3 ; b = [] ; c = [1 NaN] ;
[M,tf] = padcat(a,b,c)
% find the original NaN
[Vev,Pos] = find(tf & isnan(M))
% -> Vec = 3 , Pos = 2
This second output can also be used to change the padding value into something else than NaN.
[M, tf] = padcat(1:3,1,1:4)
M(~tf) = 99 % change the padding value into 99
Scalars will be concatenated into a single column vector.
See also cat, reshape, strvcat, char, horzcat, vertcat, isempty
nones, group2cell (Matlab File Exchange)
Jos (10584) (2021). PADCAT (https://www.mathworks.com/matlabcentral/fileexchange/22909-padcat), MATLAB Central File Exchange. Retrieved .
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Thank you for the amazing work!
how can us padcat for two dimsions array?
can the function work for cell arrays of strings?
Excelent function. Thank you Jos!
@beginner94 The description says "most releases", not "every release". Perhaps it is time for you to upgrade? Good old steam trains are also no longer running in most (sic!) countries :-)
Unfortunately it isn't really compatible with every release. I am still using R2007b and "narginchk" for example doesn't exist yet.
very useful
Very very useful. Thank you.
Super useful piece of code, especially for creating many patches with a single call.
Wonderful code. Works very well.
Excellent ... Thanks a lot
Excellent! Thank you!
works brilliantly, thank you!
Thanks!
This is really nice. However, if you get the vectors via the extractfield function from a struct and have an empty vector, there may occur a problem, if you try to concatenate this with a 1x1 matrix. The empty vector can either be 1x0 or 0x1, one of which will be the wrong size to work with.
@Jos Thanks a lot. Can you implement the same code for Cell (strings) array? When I pass a set of strings array I get the error
Conversion to double from cell is not possible.
Error in padcat (line 144)
M(M==0) = X ; % put the values in
@Jos Thanks a lot. Can you implement the same code for strings array? When I pass a set of strings array I get the error
Conversion to double from cell is not possible.
Error in padcat (line 144)
M(M==0) = X ; % put the values in
Led here by link below.
Was not disappointed.
http://stackoverflow.com/questions/41450131/matlab-create-matrix-with-mismatched-vectors/41450506#41450506
Great. Really useful for data sets with different number of points, no loop needed anymore! Thanks
File works perfectly! I second Joana's comments.
Really thank you very much... It is really what i need...
That was EXACTLY what I was looking for!
Many thanks
@German. You may want to check out the function catpad, it works on marticies and multidimensional arrrays.
http://www.mathworks.com/matlabcentral/fileexchange/33453
Nice utility, can it be modified to work with matrices and multidimensional arrays?
Works as advertised - many thanks!