Can you help me create a function according to mathematical formula?

Hello,

I am trying to create a function that will work as described below:

n = 4; %this is my input, describe how many number i will have in matrix A, but it can be any value up to 128.

A = [1, 2, 10, 16]; %input, which numbers I want to have in matrix, can be any number.

I want to divide input into 4 groups:

g1 = [];

g2 = [];

g3 = [];

g4 = [];

I want to divide it by following formula: B = sum(A) ./ n;

Which will do sum of A and divide it by n, then each value of A will be compared by B and in case " value of A < B", add this value to g1.

For example for group 1:

g1:

B = sum(A) ./ n

B = (1+2+10+16)/4

B = 7,25

Now I will compare each value of A: A(i) < B

1 < 7,25

2 < 7,25

so in this case

g1 = [1, 2];

Will do same steps for group 2 but n = 2 (because 2 numbers are already in group) and A = [10, 16]

g2:

B = sum(A) ./ n

B = (10+16)/2

B = 13

Now I will compare each value of A: A(i) < B

10 < 13

so in this case

g2 = [10];

Last step will be the same as for group 2 but if "A(i)<B" add value of A to group 3 and if "A(i) >= B" add value to group 4.

So in this case:

B = sum(A) ./ n

B = (16)/1

B = 16

16 = 16

g3 = [];

g4 = [16];

I want output to display value of each group:

In this case:

g1 = [1, 2];

g2 = [10];

g3 = [];

g4 = [16];

Thanks for any advices and tips.

[Voss]

Do you always want to end up with 4 groups, regardless of the value of n?

[Vladimir]

Yes, I always want to have 4 groups. For example:

If the input is 4 same numbers:

A = [10, 10, 10, 10]

I want to outcome to be:

g1 = [];

g2 = [];

g3 = [];

g4 = [10, 10, 10, 10];

Answer 1

[David Hill]

A=randi(128,1,20)

A = 1×20

95 39 8 114 113 87 77 105 54 128 16 114 118 13 72 28 36 97 15 40

for k=1:3
  B=sum(A)/numel(A);
  idx=A<B;
  g{k}=A(idx);
  A(idx)=[];
end
g{4}=A;
g

g = 1×4 cell array
    {[39 8 54 16 13 28 36 15 40]}    {[95 87 77 72 97]}    {[114 113 105 114]}    {[128 118]}

[Vladimir]

This one looks fine! Thanks a lot.