Categories automatically being labelled and sorted into matrix?

I currently have a table that is 635x13. If it says (code) it means I allocated it a number. My data is:

ItemID (code), Date (code), DATA1, DATA2, DATA3, DATA4, DATA5, DATA6,DATA7, DATA8, DATA9, Actual day (day-mon-year), ItemName (words).

1. How do I get Matlab to allocate my data an ID number? Can I use the ItemName instead? MatLab seems to get upset about using a written word instead of a number.
2. I need to ask Matlab to look at my ItemName, and make a matrix of all the data in the columns by that Item.

Should I be working with the data in a table? Should it be a double? I need to be able to pinpoint the individual Items ideally with words (there are thousands), and the data that corresponds with it.

I tried this:

Item1 = USEFULLDATA0211(USEFULLDATA0211(:,13) == '1', :)

but everytime I try it, MatLab gets upset about it being a cell or as table. I am unsure about how to have all my data in one.

I would love to be able to type in a request to pull the data for X item name, and get all the corresponding data, on all the different days for each.

I have been trying for weeks to solve this now, please explain it to me like I am an idiot.

Thanks :'(

[madhan ravi]

upload your table as .mat file and illustrate with a short example

Answer 1

[Star Strider]

I have no idea what characteristic distinguishes your ‘categories’. See if the findgroups (link) function will do what you want.

[Samuel Leathers]

Hello please see again, I added a bunch of info! I tried the find groups function which found the groups but didn't actually let me work with the data within those groups?

I think? Maybe I am mistaken?

Thank you!

[Star Strider]

I have no idea what you are doing.

See if using the splitapply (link) funciton will allow you to work on the groups.

Answer 2

[Peter Perkins]

It's pretty hard to understand exactly what you are trying to do from the information you have provided. One problem with what you have shown is this:

USEFULLDATA0211(:,13) == '1'

You are comparing a (one-variable) table to a char, that won't work. You need to compare the text variable in the table to the char, see the code below. Also, unless ALL of your names are one char, using == will not work, in general with char (single quotes) or cellstr (char inside of cell) you will need strcmp, so I recommend that you use strings (double quotes), again, see the code below.

>> ID = [1;1;2;2;2;1];
>> Data1 = rand(6,1);
>> Date = datetime(2019,2,1:6)';
>> Name = ["aaa";"aaa";"bbb";"bbb";"bbb";"aaa"];
>> t = table(ID,Name,Date,Data1)
t =
  6×4 table
    ID    Name        Date         Data1 
    __    _____    ___________    _______
    1     "aaa"    01-Feb-2019    0.81472
    1     "aaa"    02-Feb-2019    0.90579
    2     "bbb"    03-Feb-2019    0.12699
    2     "bbb"    04-Feb-2019    0.91338
    2     "bbb"    05-Feb-2019    0.63236
    1     "aaa"    06-Feb-2019    0.09754
>> t(t.Name == "bbb",:)
ans =
  3×4 table
    ID    Name        Date         Data1 
    __    _____    ___________    _______
    2     "bbb"    03-Feb-2019    0.12699
    2     "bbb"    04-Feb-2019    0.91338
    2     "bbb"    05-Feb-2019    0.63236