How can I create a matrix of size nxn (user input) where all outside numbers are 1, incrementally decreasing by 1 each layer the matrix goes in?

Question

Makaio 2023-3-30

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1938024-how-can-i-create-a-matrix-of-size-nxn-user-input-where-all-outside-numbers-are-1-incrementally-de

回答： Stephen23 2023-3-30

采纳的回答： Cameron

I am trying to write a code that creates something like this for a 5x5 matrix:

1 1 1 1 1

1 2 2 2 1

1 2 3 2 1

1 2 2 2 1

1 1 1 1 1

I currently have this:

rows = input('Input the amount of rows: ');

cols = input('Input the amount of columns: ');

A = [];

for r = 1:rows

for c = 1:cols

for n = 1: rows

if r == n || r == rows-n+1 || c == n || c == cols-n+1

A(r,c) = n;

fprintf('%d ', A(r,c))

end

fprintf('\n')

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

Cameron 2023-3-30

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1938024-how-can-i-create-a-matrix-of-size-nxn-user-input-where-all-outside-numbers-are-1-incrementally-de#answer_1204864

n = 5;
mymat = zeros(n);
endVal = n;
startVal = 1;
for a = 1:ceil(n/2)
    indx = startVal:endVal;
    mymat(indx,indx) = a;
    startVal = startVal + 1;
    endVal = endVal - 1;
end
disp(mymat)
     1     1     1     1     1
     1     2     2     2     1
     1     2     3     2     1
     1     2     2     2     1
     1     1     1     1     1

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。

Answer 2

Stephen23 2023-3-30

2
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1938024-how-can-i-create-a-matrix-of-size-nxn-user-input-where-all-outside-numbers-are-1-incrementally-de#answer_1204884

N = 5;
V = min(1:N,N:-1:1);
M = min(V,V.')
M = 5×5
     1     1     1     1     1
     1     2     2     2     1
     1     2     3     2     1
     1     2     2     2     1
     1     1     1     1     1