Create table columns with some entries blank (no quote symbols)

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I have a table with some Boolean variables. They show up as `true` or `false`. I would like the trues to show up as (say) "Y" and the falses to show up as blanks. It's easier to see patterns.
I tried replacing the Boolean columns with columns of type `string`, but each string is adorned with quotes, even the blank ones. Too much visual noise. Same if I use a cell array of char arrays.
I often have good luck by applying `categorical` to string columns to get rid of quotes, but that doesn't work when there are empty strings or single spaces (" ").
Is there any way to have table columns with text labels, but some blanks without quotes?
I am using Matlab 2019a. Here it is, using string column arrays. I get similar results with cell column arrays of char arrays.
>> Tab = table;
>> Tab.YesNo1 = [false;true];
>> Tab.YesNo2 = strings( height( Tab ), 1 )
>> Tab.YesNo2( Tab.YesNo1 ) = "Y"
YesNo1 YesNo2
______ ______
false ""
true "Y"
>> Tab.YesNo2 = categorical( Tab.YesNo2 )
YesNo1 YesNo2
______ ___________
false <undefined>
true Y
>> Tab.YesNo2 = repmat(" ", height( Tab ), 1 );
>> Tab.YesNo2( Tab.YesNo1 ) = "Y"
YesNo1 YesNo2
______ ______
false " "
true "Y"
>> Tab.YesNo2 = categorical( Tab.YesNo2 )
YesNo1 YesNo2
______ ___________
false <undefined>
true Y
  1 Comment
AndresVar on 29 Mar 2022
Can you give example? Is this what you mean?
a = [true; false];
t = table(a) % table with logicals
t = 2×1 table
a _____ true false
b = repmat("",size(a)); % test with string
c = repmat(' ',size(a)); % test with char
idxTrue = t.a==true; % get position of true values
b(idxTrue) = "Y";
c(idxTrue) = 'Y';
% add the new columns
t.b = b;
t.c = c;
t = 2×3 table
a b c _____ ___ _ true "Y" Y false ""
It still may not be effective to look visualize the table in the printed format, maybe you should plot something?

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Answers (1)

Arif Hoq
Arif Hoq on 29 Mar 2022
try this:
for i=1:size(col,1)
if string(table2array(T(i,1))) ==string({'True'})
FM on 29 Mar 2022
Edited: FM on 29 Mar 2022
I added my sample code and output to the posted question.
I get what you say about plotting, but I'm trying to accomplish something simple without taking the level of effort to the next level. Otherwise, it's not worth it and I have to live with the visual noise.
For example, I could copy and paste it into Vim and use it's editorial powers.
I could copy and paste it into LaTeX and use Vim's editorial powers.
I could go through COM and dump the table into a spreadsheet, where the unicode characters might render.
I'm hoping that there is a solution for proper formatting in the command window.
AFTERNOTE: I'm finding that if the entire column is a single char array, the quotes don't show. But monolithic char arrays are not easy to deal with. You have to take into account space padding in equality testing, and the code to change a single row is uglier. Hoping there is a better solution.

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