Look up a value in another array

3 次查看（过去 30 天）
Aaron
Aaron 2013-11-12
评论： Aaron 2013-11-13
I have one array which lists the max values for column of column B for each unique item in column A as follows:
'888888888888888888880001' -40
'888888888888888888880002' -47
I have the following array and I would like to find the column A and column B that match with the first row in the above array, and create a new array which adds the column C value for: '888888888888888888880001' -40 to the array. Then do the same thing for the second row in the table above and add it to the same array.
'888888888888888888880001' -66 9
'888888888888888888880001' -52 10
'888888888888888888880001' -47 20
'888888888888888888880001' -56 26
'888888888888888888880001' -47 38
'888888888888888888880001' -51 42
'888888888888888888880001' -40 47
'888888888888888888880001' -40 54
'888888888888888888880002' -50 44
'888888888888888888880002' -47 57
The result of this should be an array of 2 rows:
'888888888888888888880001' -40 47
'888888888888888888880002' -47 57
There are two places that have -40 and I just need it to have either of those values in the final array, but not both.
Any help would be greatly appreciated. Thanks.

请先登录，再回答此问题。

采纳的回答

Andrei Bobrov
Andrei Bobrov 2013-11-12
编辑：Andrei Bobrov 2013-11-12
EDIT
d1 = [data(:,1), cellfun(@num2str,data(:,2),'un',0)];
a1 = [A(:,1),cellfun(@num2str,A(:,2),'un',0)];
[lk,i2] = ismember(data(:,1),A(:,1));
d1 = [i2(lk) cell2mat(data(lk,2:3))];
a1 = [(1:size(A,1))', cell2mat(A(:,2))];
[lc2,ii2] = ismember(d1(:,1:2),a1,'rows');
data1 = data(lc2,:);
% corrected below
idx = accumarray(ii2(lc2),(1:size(d1(lc2,:),1))',[],@(x)x(randi(numel(x))));
out = data1(idx,:);
  5 个评论
显示 3更早的评论
Aaron
Aaron 2013-11-12
Thank you very much! It was very helpful. If you wouldn't mind, could you look at the main question that I had for this data. I asked the question at the following link:
http://www.mathworks.com/matlabcentral/answers/105879-how-to-remove-unwanted-values-from-an-array
It is the last thing I have to do with this data and would help me out a lot.
Aaron
Aaron 2013-11-13
And I made it look like a long question but it is really the same question as the one I just asked on this one, only it involves using the standard deviation to remove unwanted rows

请先登录，再进行评论。

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Characters and Strings 的更多信息

标签

Community Treasure Hunt

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

Start Hunting!

Translated by