How to implement Multi Poynomial Interpolation - X,Y dependent table

Hi,

I am trying to implement a Multivariate Polynomial Interpolation for a table which depend on Alpha (from -10 to 10) and beta (from -30 to 30).

My idea is two implement:

• Curve fitting by
• Successive univariate polynomial interpolaton by

I WANT TO IMPLEMENT THIS IN CODE TO BE ABLE TO USE IT IN OTHER PROGRAMS

Image of the table:

So far I have found a useful code to perform polyfit by the Vandermonde Matrix

https://www.mathworks.com/matlabcentral/answers/251243-can-we-do-polyfit-on-matrix

surface(matrix);

alpha=[-10 -5 0 -5 -10];

beta=[-30 -25 -20 -15 -10 -9 -6 -4 -2 0 2 4 6 8 10 15 20 25 30];

matrix=[...

-0.02 -0.0036 -0.0107 -0.0334 -0.0778 -0.0944 -0.0926 -0.0855 -0.0815 -0.0835 -0.0955 -0.093 -0.0943 -0.0881 -0.0743 -0.0265 -0.004 0.0034 0.0268

-0.0153 -0.0385 -0.0525 -0.0743 -0.1233 -0.1376 -0.1466 -0.1551 -0.1663 -0.1719 -0.1683 -0.1568 -0.1437 -0.1371 -0.1295 -0.0798 -0.0589 -0.0445 -0.0241

-0.0549 -0.0792 -0.0932 -0.1226 -0.1521 -0.1609 -0.1688 -0.1774 -0.188 -0.2153 -0.1839 -0.1738 -0.1648 -0.1594 -0.1525 -0.1225 -0.0931 -0.1276 -0.058

-0.112 -0.124 -0.152 -0.168 -0.183 -0.188 -0.191 -0.192 -0.189 -0.1888 -0.19 -0.193 -0.192 -0.191 -0.183 -0.168 -0.152 -0.125 -0.112

-0.117 -0.127 -0.152 -0.159 -0.16 -0.16 -0.159 -0.157 -0.162 -0.161 -0.162 -0.163 -0.167 -0.162 -0.162 -0.162 -0.153 -0.126 -0.117

-0.105 -0.133 -0.144 -0.155 -0.155 -0.155 -0.155 -0.155 -0.158 -0.1606 -0.161 -0.162 -0.157 -0.157 -0.156 -0.156 -0.145 -0.133 -0.118

-0.097 -0.112 -0.122 -0.135 -0.142 -0.142 -0.151 -0.153 -0.157 -0.1548 -0.155 -0.152 -0.153 -0.145 -0.146 -0.14 -0.126 -0.117 -0.104

-0.097 -0.118 -0.133 -0.151 -0.152 -0.15 -0.155 -0.155 -0.152 -0.1452 -0.148 -0.155 -0.155 -0.157 -0.152 -0.151 -0.134 -0.118 -0.096

-0.062 -0.083 -0.097 -0.106 -0.134 -0.142 -0.138 -0.134 -0.13 -0.1264 -0.126 -0.126 -0.151 -0.161 -0.166 -0.137 -0.126 -0.115 -0.094

-0.075 -0.103 -0.113 -0.108 -0.137 -0.144 -0.153 -0.154 -0.154 -0.153 -0.155 -0.15 -0.15 -0.16 -0.164 -0.133 -0.138 -0.129 -0.099 ];

Any idea will be very welcome!

Thanks :)