MATLAB: Indexing and replacing value in a zero matrix based on a table

indexinginserting valuesMATLABmatrix array

Hello,

I am trying to input a value in a zeros matrix of size 11*10. This is based on a variable which has three columns (Number, ID, ANS) as shown below. Now I want to insert the value in ANS which is -1 in the zeros matrix at 10×5 (ID x Number) position (index). Any suggestion on how this can be done?

Number ID ANS

5 10 -1

Best Answer

If your Number and ID and ANS are scalar then

YourMatrix(Number, ID) = ANS;

If they are vectors then there are multiple approaches, including:

YourMatrix( sub2ind(size(YourMatrix), Number(:), ID(:)) ) = ANS(:);

YourMatrix = YourMatrix + accumarray( Number(:), ID(:), ANS(:), size(YourMatrix) );

and there are approaches using sparse.

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num2str(uint64(14472334024676221),'%u')

You have exceeded flintmax:

flintmax Largest consecutive integer in floating point format.
  flintmax returns the largest consecutive integer in IEEE double
  precision, which is 2^53. Above this value, double precision format
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MATLAB: I have 2D array of size 16*16 stored in a variable temp and I have set of x and y values x=[1 2 3]; y=[4 5 6]; I want to extract values from temp variable indexed by (x,y)=(1,4) (2,5) (3,6) without using for loop. Thank you.

values = YourMatrix( sub2ind(size(YourMatrix), x, y) );

The faster form of this for a 16 x 16 matrix is

YourMatrix(x + (y-1)*16)

Best Answer

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MATLAB: How to avoid the loss of the last digit (it gives a zero instead of a one)

MATLAB: I have 2D array of size 16*16 stored in a variable temp and I have set of x and y values x=[1 2 3]; y=[4 5 6]; I want to extract values from temp variable indexed by (x,y)=(1,4) (2,5) (3,6) without using for loop. Thank you.

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