Duplicate the element n times for specific dimension

Dear all,

I have a matix. The size is 22x15x30x4000 (316800000 double)

I would average the elements in last dimension between 1001:3000, and duplicate this value 4000 times in the last dimension. The size is also 22x15x30x4000.

Could anyone help me?

[madhan ravi]

Small illustration might help.

Answer 1

[Rik]

Use subindexing, the mean function, and repmat.