Suppose I have a matrix of size(3,3).This is up-scaled by 2 making it (6,6).So there would be a number of vacant values between each element of the initial (3,3) matrix.Then how do you fill up the 0 values in addmatrixR by bicubic/liner interpolation

Question

MSP 2017-7-17

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/349101-suppose-i-have-a-matrix-of-size-3-3-this-is-up-scaled-by-2-making-it-6-6-so-there-would-be-a-numb

编辑： Stephen23 2017-7-17

prevR=magic(3)
m=1;
   k1=1
addRmatrix= zeros(2*size(prevR,1),2*size(prevR,2))
      for i=1:size(prevR,1);
          for j=1:size(prevR,2);
          addRmatrix(m,k1)= prevR(i,j); 
          k1=k1+2   ; 
          end
      m=m+2;
      k1=1;
      end

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Stephen23 2017-7-17

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/349101-suppose-i-have-a-matrix-of-size-3-3-this-is-up-scaled-by-2-making-it-6-6-so-there-would-be-a-numb#answer_274470

编辑：Stephen23 2017-7-17

在 MATLAB Online 中打开

Just use interp2:

>> M = magic(3)
M =
   8   1   6
   3   5   7
   4   9   2
>> interp2(M,1)
ans =
   8.0000   4.5000   1.0000   3.5000   6.0000
   5.5000   4.2500   3.0000   4.7500   6.5000
   3.0000   4.0000   5.0000   6.0000   7.0000
   3.5000   5.2500   7.0000   5.7500   4.5000
   4.0000   6.5000   9.0000   5.5000   2.0000

Or the simplest of all:

>> interp2(M)
ans =
0000   4.5000   1.0000   3.5000   6.0000
5000   4.2500   3.0000   4.7500   6.5000
0000   4.0000   5.0000   6.0000   7.0000
5000   5.2500   7.0000   5.7500   4.5000
0000   6.5000   9.0000   5.5000   2.0000

If you need to specify the sample points, then do something like this:

>> [Xi,Yi] = meshgrid(1:1.0:S(2),1:1.0:S(1));
>> [Xo,Yo] = meshgrid(1:0.5:S(2),1:0.5:S(1));
>> out = interp2(Xi,Yi, M, Xo,Yo)
out =
   8.0000   4.5000   1.0000   3.5000   6.0000
   5.5000   4.2500   3.0000   4.7500   6.5000
   3.0000   4.0000   5.0000   6.0000   7.0000
   3.5000   5.2500   7.0000   5.7500   4.5000
   4.0000   6.5000   9.0000   5.5000   2.0000

4 个评论
显示 2更早的评论隐藏 2更早的评论

MSP 2017-7-17

编辑：MSP 2017-7-17

Thanks a lot,But could you elaborate the third code for me. What does Xo and Yo specify

Stephen23 2017-7-17

编辑：Stephen23 2017-7-17

@MSP: Xi and Yi are sample locations of the input data values: I defined these arbitrarily to be with steps of one. Xo and Yo are the sample locations of the output data values: I defined these to have half the step size of the input steps (steps of 0.5).

请先登录，再进行评论。

Answer 2

C.J. Harris 2017-7-17

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/349101-suppose-i-have-a-matrix-of-size-3-3-this-is-up-scaled-by-2-making-it-6-6-so-there-would-be-a-numb#answer_274471

在 MATLAB Online 中打开

Just use interp2 on the original matrix, like so:

prevR = magic(3)
ans =
       8     1     6
       3     5     7
       4     9     2
addRmatrix = interp2(prevR,1)
ans =
    8.0000    4.5000    1.0000    3.5000    6.0000
    5.5000    4.2500    3.0000    4.7500    6.5000
    3.0000    4.0000    5.0000    6.0000    7.0000
    3.5000    5.2500    7.0000    5.7500    4.5000
    4.0000    6.5000    9.0000    5.5000    2.0000