How to create string of text-objects
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Hi, I have the following matrix as an output. I wouldlike to make a third column such that the rows corresponding to 1, i would like to write "paid" and the rows corresponding to 0 I would like to write "not paid" so that the resulting table should have three columns, the first two columns are columns of the matrix D and the third should contain either "paid" or "not paid". I have inserted the expected output. The second matrix I have inesrted the column mannualy. Please help.
D =
13 0
4 1
5 1
1 1
2 1
3 1
14 0
5 1
16 0
7 1
8 1
9 1
3 1
4 1
2 1
1 1
3 1
98 0
100 0
what i expect is;
D =
13 0 Notpaid
4 1 paid
5 1 paid
1 1 paid
2 1 paid
3 1 paid
14 0 Notpaid
5 1 paid
16 0 Notpaid
7 1 paid
8 1 paid
9 1 paid
3 1 paid
4 1 paid
2 1 paid
1 1 paid
3 1 paid
98 0 Notpaid
100 0 Notpaid
Accepted Answer
More Answers (2)
chicken vector
on 26 Apr 2023
You can't concatenate doubles and string in one array, because the array can be only one of them.
If you want to only store the information you can use cells:
D = [randi(100,20,1),rand(20,1)>=0.5];
result = cell(2,1);
result{1} = D;
result{2} = strings(length(D),1);
for j = 1 : length(D)
if ~D(j,2)
result{2}(j) = "Notpaid";
else
result{2}(j) = "Paid";
end
end
If it's for display purposes you can transform everything into a string:
D = [randi(100,20,1),rand(20,1)>=0.5];
result = strings(length(D),3);
result(:,1:2) = string(D);
for j = 1 : length(D)
if ~D(j,2)
result(j,3) = "Notpaid";
else
result(j,3) = "Paid";
end
end
4 Comments
To eliminate the loop construct and explicit if...else clause, "the MATLAB way" would be to use a lookup table and vectorize...
CODE={'Notpaid';'Paid'}; % the lookup values
D=num2cell(D); % convert original to cell array to add disparate type
D(:,3)=CODE([D{:,2}]+1) % add the third column based on second [0,1]==>[1,2] index
chicken vector
on 26 Apr 2023
My usual way of doing it would be to:
paidIdx = D(:,2) == 1;
D(paidIdx,3) = "Paid";
D(~paidIdx,3) = "Notpaid";
But your approach is much better.
dpb
on 26 Apr 2023
I don't know that it's "much" better, but does illustrate using the lookup table approach that many novices may have not seen...it trades one temporary variable for another so isn't a tremendous advantage one way or another other than, perhaps, putting the constants into one array so can just adjust it if number of choices changes.
chicken vector
on 26 Apr 2023
Aesthetically much better*
Dyuman Joshi
on 26 Apr 2023
Edited: Dyuman Joshi
on 26 Apr 2023
Given the format of your final output, you will either have to use string arrays, cell arrays or categorical arrays.
%Categorical array method
D =[13 0
4 1
5 1
1 1
2 1
3 1
14 0
5 1
16 0
7 1
8 1
9 1
3 1
4 1
2 1
1 1
3 1
98 0
100 0];
%Values corresponding to paid
idx = D(:,2);
%Convert D to a categorical array
D = categorical(D);
str = categorical(["Notpaid", "paid"]);
D(:,3) = str(idx+1)
1 Comment
dpb
on 26 Apr 2023
Actually, the categorical is better choice than the string... +1
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