Comparing array with any element of the array

Hello All.

I have vector named classes

classes =

     1
     2

I need to compare all classes element with

D = dataset(dataset(:,p)==X,:);

Briefly equation above should compareing with all classes elements, for my example X should be 1 or 2

X can be any element of classes vector, in my code i compare p th element of the dataset array with X , X is one of the elemeny of classes vector.

I just create a example classes matrix it can be any array.

[Guillaume]

Your question is very unclear. All we know is that you have two things. One looks like it is a vector called classes, the other is a 2D matrix called D. Incidentally all the values in column p of D are all equal to X, but it doesn't sound like it's relevant.

It's unclear what 'compare' means in this context, so please provide an example of all inputs and desired output.

[betul uslu]

You are right, it is very hard to explain, but i will try, for example X can be any element of classes vector, in my code i compare p th element of the dataset array with X , X is one of the elemeny of classes vector. I use compare for equality 1,2 can be equal to X.

[Guillaume]

As I wrote please provide an example of all inputs and desired output.

[betul uslu]

I have dataset called 'dataset'

I also have a vector calles 'classes'

classes =
     1
     2

I generate classes vector from my dataset,

I need do divide my dataset in to number of element of classes vector (for my example i need to divide 2). To do this i use.

     D = dataset(dataset(:,p)==X,:);

X on the above code is members in 'classes vector'

What i need is;

I need to divide 2 parts to my matrix 'dataset' order of dividing is; Matrices that their 4th (p th) colums are equal to 1 and 4th (p th) colums are equal to 2. That 1 and 2 should be coming from 'classes' vector .

Disire output is

First matrix

Second matrix

I hope i can explain everything briefly.

Answer 1

[Guillaume]

Ok, now I understand what you want to do.

Note that datasets have been deprecated for a while and it's recommended you use tables instead. I'm not familiar with datasets and I don't have the toolbox so the following is for tables. You can easily transform your dataset into a table with dataset2table.

First, I'll note that typically splitting a table into several tables is rarely useful. Matlab has plenty of functions that allows you to perform group statistics according to a particular column. These work on a single table. See groupsummary, grouptransform, groupfilter, etc.

If you really want to split the table into multiple tables:

g = findgroup(yourtable(:, p));
splittables = splitapply(@(rows) {yourtable(rows, :)}, (1:height(yourtable)).', g);  %split table into cell array of tables

[betul uslu]

Actually i need to use dataset because it is my project and lecturer wants datasets.

[Guillaume]

a) Go back to your lecturer and tell him to move on with the time. datasets have long been deprecated and don't have as many useful features as tables.

b) You can trivially convert tables back to dataset with table2dataset