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.
Hope this helps!
