how to form a covariance matrix ? for the following how to create covariance matrix b/w INSAT_Data and RAOB Data.

clear all; close all; clc; filename='3RSND_RAOB_2017.h5'; file_id =H5F.open(filename); finfo=h5info(filename); A=hdf5read(filename,'3RSND_PRES'); B(1)=A(11,1); B(2)=A(13,1); B(3)=A(15,1); B(4)=A(16,1); B(5)=A(18,1); B(6)=A(20,1); B(7)=A(23,1); B(8)=A(24,1); B(9)=A(25,1); B(10)=A(26,1); B(11)=A(28,1); B(12)=A(31,1); B(13)=A(35,1); B(14)=A(38,1); B(15)=A(40,1); Data1=hdf5read(filename,'3RSND_TEMP_FG'); INSAT_Data =Data1([11 13 15 16 18 20 23:25 26 28 32 35 38 40],:); Data2=hdf5read(filename,'RAOB_TEMP'); RAOB_Data =Data2([2:16],:);