From .csv to .mat, matrix indexing

Hello,

I am trying to convert a .CSV file to .mat in matlab. I have attached the .CSV file. In the file the columns D,E,F,G which is marked has values like 8,2,7,13 which should belong to a field name called labelfacegrid. Here's the code i have written so far.

clc;
close all;
clear all;
T = readtable('E:/Metadata_create.csv','ReadVariableNames',false);
frameIndex = T{:,1};
labelDotXCam = T{:,2}; 
labelDotYCam = T{:,3}; 
labelFaceGrid0 = T{:,4};
labelFaceGrid1 = T{:,5};
labelFaceGrid2 = T{:,6};
labelFaceGrid3 = T{:,7};
labelRecNum = T{:,8};
labelTest = T{:,9}; 
labelTrain = T{:,10}; 
labelVal = T{:,11};
save('E:/mymat.mat','frameIndex', 'labelDotXCam', 'labelDotYCam', 'labelFaceGrid0','labelFaceGrid1','labelFaceGrid2','labelFaceGrid3', 'labelRecNum', 'labelTest', 'labelTrain', 'labelVal')

As seen above i have put variable name as labelFaceGrid0,labelFaceGrid1,labelFaceGrid2,labelFaceGrid3 for now but in reality i want it to be a single variable with 4 different values like as in csv file the columns D,E,F,G. What code changes should i make to accomodate those four values for a single variable or a field name. I am stuck. Thank you.

[Walter Roberson]

https://www.mathworks.com/help/matlab/ref/table.mergevars.html

[Madan Kumar Y]

Hey Walter,

Thank you will give a try.

[Madan Kumar Y]

Hey Walter,

looks like mergevars isn't supported in the version of matlab i have that is R2014a. Any other alternatives??.

Thanks,

Madan

[Ankit]

Hello Madan,

first recommendations is to avoid using clear all;

You can save your variables in structure format as mentioned below. Is it that what you are looking for?

clc;
close all;
T = readtable('E:/Metadata_create.csv','ReadVariableNames',false);
frameIndex = T{:,1};
labelDotXCam = T{:,2}; 
labelDotYCam = T{:,3}; 
labelFaceGrid.a = T{:,4};
labelFaceGrid.b = T{:,5};
labelFaceGrid.c = T{:,6};
labelFaceGrid.d = T{:,7};
labelRecNum = T{:,8};
labelTest = T{:,9}; 
labelTrain = T{:,10}; 
labelVal = T{:,11};
save('E:/mymat.mat','frameIndex', 'labelDotXCam', 'labelDotYCam', 'labelFaceGrid', 'labelRecNum', 'labelTest', 'labelTrain', 'labelVal')

Thanks

Ankit

Answer 1

[Guillaume]

Not exactly sure what you're asking, is it simply?

labelFaceGrid = T{:, 4:7};  %extract column 4 to 7 as a matrix

[Madan Kumar Y]

Hey Guillaume,

yeah something like that, but it's throwing error in save, like saying variable 'labelFaceGrid' not found.

Thanks,

Madan

[Ankit]

have you change the variable name that you are saving from "labelFaceGrid0" ... to labelFaceGrid ?

[Guillaume]

Show us the exact code you're using now, then. Obviously if you've created a labelFaceGrid variable as above, save is not going to complain that it doesn't exist, so you must have done something different.

[Madan Kumar Y]

Hey Ankith,

Ya i have done that. whatever variable i am assigning, the same i am using it in save.

Thanks,

Madan

[Ankit]

@Guillaume he is saving the *.mat file as follows I just change the name from labelFaceGrid to labelFaceGrid1 (see below)

save('E/mymat.mat','frameIndex', 'labelDotXCam', 'labelDotYCam', 'labelFaceGrid1', 'labelRecNum', 'labelTest', 'labelTrain', 'labelVal')

Following error matlab throws:

Error using save
Variable 'labelFaceGrid1' not found.

as Mr. Guillaume mentioned could you please post your code and error please?

[Madan Kumar Y]

Hey Guillaume,

Gracias, it worked. There was a spelling mistake, my bad :/ .

Hey ankit,

Thanks for the suggestions, it was helpful.

Thanks,

Madan