Mean of a repeating numbers corresponding values

I have a matrix like [ 10 40; 10 60 ;10 90; 14 10; 14 20; 14 30; 14 40] i want to calculate the mean of the repeating numbers corresponding values like repeating 10 corresponding values are 40 60 90 so the mean is 190/3 and similarly the 14 corresponding values are 10 ,20,30,40 so the mean is 100/4. How can i do this ?

Answer 1

[Simon Chan]

Use function groupsummary:

A = [ 10 40; 10 60 ;10 90; 14 10; 14 20; 14 30; 14 40];
T = table(A(:,1),A(:,2),'VariableName',{'Item','Value'});
S = groupsummary(T,'Item','mean')

S = 2×3 table
    Item    GroupCount    mean_Value
    ____    __________    __________

     10         3           63.333  
     14         4               25  

[Sandeep Nair]

am using 2017 version of matlab, i cannot find group summary function in it

[Sandeep Nair]

Is there any other method instead of using table

[Simon Chan]

A = [ 10 40; 10 60 ;10 90; 14 10; 14 20; 14 30; 14 40];
Item = A(:,1);
Value = A(:,2);
[UItem,~] = unique(Item);
meanValue = arrayfun(@(x) mean(Value(ismember(Item,x))),UItem);
result = [UItem, meanValue]

result = 2×2

10.0000 63.3333 14.0000 25.0000

[Image Analyst]

@Sandeep Nair you can use splitapply(), introduced in 2015b.