MATLAB Answers

How can I seperate these number from a cell and put it into a matrix.

16 views (last 30 days)
Hai Luu
Hai Luu on 14 Feb 2020
Commented: Star Strider on 15 Feb 2020
I have tried systax "cell2mat" but it didnt work.


Star Strider
Star Strider on 14 Feb 2020
You will have to provide (attach) that file if you want help with it. I was able to find it online although not able to download it.

Sign in to comment.

Accepted Answer

Star Strider
Star Strider on 14 Feb 2020
Try this:
[num,txt,raw] = xlsread('2019_nC0v_20200121_20200126_cleaned.xlsx');
vars = regexp(txt(1,:), ',', 'split');
varsc = string(vars{:})
newcell = regexp(txt(2:end), ',', 'split');
C1 = cellfun(@(x)str2double(x(:,1)), newcell);
C2 = cellfun(@(x)x(:,2), newcell);
C3 = cellfun(@(x)x(:,3), newcell);
C4 = datetime(cellfun(@(x)x(:,4), newcell), 'InputFormat','MM/dd/yyyy');
for k = 1:4
C(:,k) = cellfun(@(x)str2double(x(:,k+4)), newcell);
COVID19 = table(C1,C2,C3,C4,C(:,1),C(:,2),C(:,3),C(:,4));
COVID19.Properties.VariableNames = {'Nr','Province/State','Country','Date Last Updated','Confirmed','Suspected','Reecovered','Deaths'};
Check = COVID19(1:5,:)
Check =
Nr Province/State Country Date Last Updated Confirmed Suspected Reecovered Deaths
__ ______________ __________________ _________________ _________ _________ __________ ______
0 {'Shanghai'} {'Mainland China'} 21-Jan-2020 9 10 0 0
1 {'Yunnan' } {'Mainland China'} 21-Jan-2020 1 0 0 0
2 {'Beijing' } {'Mainland China'} 21-Jan-2020 10 0 0 0
3 {'Taiwan' } {'Taiwan' } 21-Jan-2020 1 0 0 0
4 {'Jilin' } {'Mainland China'} 21-Jan-2020 0 1 0 0
I cannot get the variable names to import correctly or parse correctly. I added them manually.


Show 2 older comments
Star Strider
Star Strider on 15 Feb 2020
I tried that first.
To use that approach, do this:
Cc = cellfun(@(x)str2double(x(:,5:8)),newcell, 'Uni',0);
C = cell2mat(Cc);
The rest of the code is unchanged, with these two assignments replacing the loop. I am not certain which is more efficient.
Hai Luu
Hai Luu on 15 Feb 2020
Cool. Any possible way to classify the people come from Main Land, Taiwan,.... for instance.?
Star Strider
Star Strider on 15 Feb 2020
I am not certain what you mean by ‘classify’. If you want to assign numbers to them, use the findgroups function.
For example —
CountryID = findgroups(COVID19(:,3));
You can do the same for 'Province/State' by referring to column 2 instead.
To combine them, use either of these:
CountryStateID = findgroups(COVID19(:,[2 3]));
CountryStateID = findgroups(COVID19(:,2), COVID19(:,3));
Both produce the same result.
There are other options as well. See: Grouping and Binning Data in the Preprocessing Data documentation section.

Sign in to comment.

More Answers (1)

Jon on 14 Feb 2020
You will not be able to put your data from the cell array you show to a matrix because you have both numeric and non-numeric data in your cell array and a MATLAB matrix can be either numeric or non-numeric but not both.
I suggest instead that you store your data in a table where it will be very natural to work with it


Hai Luu
Hai Luu on 15 Feb 2020
the reason I want to put it into a matrix is because I want to do something with machine learning :D. I have tried put numbers like this file but with systax cell2mat, I still cannot put it into a matrix.

Sign in to comment.

Sign in to answer this question.

Translated by