cvpartition object with manual input

I want to be able to define manually/beforehand which indices go to train and which ones go to test in the cvpartition object.

How can I achieve this?

Answer 1

[Prince Kumar]

Hi,

You can slice the data as per your need.

Look at the following example :

load ionosphere
v2 = X(1:4,:);
v2 = [v2; X(10:14,:)];
disp(v2);

  Columns 1 through 22

    1.0000         0    0.9954   -0.0589    0.8524    0.0231    0.8340   -0.3771    1.0000    0.0376    0.8524   -0.1776    0.5976   -0.4495    0.6054   -0.3822    0.8436   -0.3854    0.5821   -0.3219    0.5697   -0.2967
    1.0000         0    1.0000   -0.1883    0.9304   -0.3616   -0.1087   -0.9360    1.0000   -0.0455    0.5087   -0.6774    0.3443   -0.6971   -0.5169   -0.9751    0.0550   -0.6224    0.3311   -1.0000   -0.1315   -0.4530
    1.0000         0    1.0000   -0.0336    1.0000    0.0049    1.0000   -0.1206    0.8897    0.0120    0.7308    0.0535    0.8544    0.0083    0.5459    0.0030    0.8377   -0.1364    0.7553   -0.0854    0.7089   -0.2750
    1.0000         0    1.0000   -0.4516    1.0000    1.0000    0.7122   -1.0000         0         0         0         0         0         0   -1.0000    0.1452    0.5409   -0.3933   -1.0000   -0.5447   -0.6997    1.0000
    1.0000         0   -0.0186   -0.0846         0         0         0         0    0.1147   -0.2681   -0.4566   -0.3817         0         0   -0.3366    0.3860   -0.3713    0.1502    0.6373    0.2212         0         0
    1.0000         0    1.0000    0.0665    1.0000   -0.1839    1.0000   -0.2732    1.0000   -0.4311    1.0000   -0.4135    0.9623   -0.5187    0.9071   -0.5902    0.8923   -0.6647    0.6988   -0.7100    0.7065   -0.7632
    1.0000         0    1.0000   -0.5421    1.0000   -1.0000    1.0000   -1.0000    1.0000    0.3622    1.0000   -0.4112    1.0000    1.0000    1.0000   -1.0000    1.0000   -0.2935    1.0000   -0.9360    1.0000    1.0000
    1.0000         0    1.0000   -0.1632    1.0000   -0.1017    1.0000   -0.1520    1.0000   -0.1928    0.9405   -0.3515    0.9574   -0.2979    0.9372   -0.3441    0.9449   -0.2811    0.9014   -0.4338    0.8604   -0.4731
    1.0000         0    1.0000   -0.8670    1.0000    0.2228    0.8549   -0.3990    1.0000   -0.1209    1.0000    0.3515    1.0000    0.0777    1.0000   -0.1477    1.0000   -1.0000    1.0000   -1.0000    0.6183    0.1580

  Columns 23 through 34

    0.3695   -0.4736    0.5681   -0.5117    0.4108   -0.4617    0.2127   -0.3409    0.4227   -0.5449    0.1864   -0.4530
   -0.1806   -0.3573   -0.2033   -0.2657   -0.2047   -0.1840   -0.1904   -0.1159   -0.1663   -0.0629   -0.1374   -0.0245
    0.4339   -0.1206    0.5753   -0.4022    0.5898   -0.2215    0.4310   -0.1736    0.6044   -0.2418    0.5605   -0.3824
         0         0    1.0000    0.9070    0.5161    1.0000    1.0000   -0.2010    0.2568    1.0000   -0.3238    1.0000
         0         0   -0.1480   -0.0133    0.2064   -0.0229         0         0    0.1659    0.2409   -0.0821    0.3806
    0.6308   -0.8054    0.5587   -0.8913    0.4721   -0.8650    0.4030   -0.8367    0.3100   -0.8909    0.2299   -0.8916
    1.0000    1.0000    1.0000   -0.4089    1.0000   -0.6274    1.0000   -1.0000    1.0000   -1.0000    1.0000   -1.0000
    0.8299   -0.5122    0.8408   -0.4714    0.7622   -0.5837    0.6572   -0.6879    0.6871   -0.6454    0.6473   -0.6723
    1.0000    0.6235    1.0000   -0.1701    1.0000    0.3592    1.0000   -0.6649    1.0000    0.8843    1.0000   -0.1883

Here "v2" will contain the data with your choice of indices.

For more information please look indexing documentation.

Hope this helps!