Search matrix for array of values and place results into another

2 ビュー (過去 30 日間)
lightroman
lightroman 2018 年 2 月 27 日
回答済み: Andrei Bobrov 2018 年 2 月 28 日
I am attempting to search mat A for values B. Then take the indices where B is located in A and access the corresponding indices in mat C. Once the values are accessed from C they need to be brought to a front of each row and the rest of the row filled with -1, I can do this with for loops and binary operators or is member function, but it takes a very long time. The pattern is shown below and should be identifiable from looking at it.
if true
A = [ 2 87 35 9 82 3;
77 6 7 92 14 5;
98 64 4 8 33 17;
71 7 54 34 2 8;
9 1 13 18 2 7]
B = 1:10
C = [ 44 32 2 13 22 98;
67 43 87 67 46 23;
87 34 55 22 13 8;
3 98 76 23 29 4;
87 66 43 26 83 23]
Out = [ 44 13 98 -1 -1 -1;
43 87 23 -1 -1 -1;
55 22 -1 -1 -1 -1;
98 29 4 -1 -1 -1;
87 66 83 23 -1 -1]
end

採用された回答

Stephen23
Stephen23 2018 年 2 月 27 日
編集済み: Stephen23 2018 年 2 月 27 日
>> A = [2,87,35,9,82,3;77,6,7,92,14,5;98,64,4,8,33,17;71,7,54,34,2,8;9,1,13,18,2,7];
>> B = 1:10;
>> C = [44,32,2,13,22,98;67,43,87,67,46,23;87,34,55,22,13,8;3,98,76,23,29,4;87,66,43,26,83,23];
>> idm = ismember(A,B);
>> D = C;
>> D(~idm) = -1;
>> [~,idc] = sort(idm,2,'descend');
>> S = size(D);
>> idr = ndgrid(1:S(1),1:S(2));
>> idx = sub2ind(S,idr,idc);
>> D = D(idx)
D =
44 13 98 -1 -1 -1
43 87 23 -1 -1 -1
55 22 -1 -1 -1 -1
98 29 4 -1 -1 -1
87 66 83 23 -1 -1

その他の回答 (1 件)

Andrei Bobrov
Andrei Bobrov 2018 年 2 月 28 日
t = ismember(A',B);
Ct = C';
ii = sort(t,'descend');
out = double(ii);
out(ii) = Ct(t);
out(~ii) = -1;
out = out';

カテゴリ

Help Center および File ExchangeResizing and Reshaping Matrices についてさらに検索

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by