you should really be more clear about what 'some issue' is. if you got an error message, tell us the exact error message.
you shouldn't have to declare abc_p. that loop will assign element by element into abc_p, expanding it each time the size needs to increase for the assignment. this could get very slow for large arrays, as you are creating a copy of abc_p every time it needs to expand the size.
And it seems that all this series of loops is doing is copying the values of period_arr straight into abc_p, up to the range limits defined by all of the length() statements. You could simply calculate the lengths and then do a direct copy of a subset of period_arr.
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>> edit
>> A = rand(4,3,4,3)
A =
ans(:,:,1,1) =
0.394286 0.983926 0.544054
0.977536 0.225626 0.465681
0.202869 0.430088 0.517584
0.345954 0.069145 0.396835
ans(:,:,2,1) =
0.596955 0.432200 0.266274
0.029700 0.441046 0.607404
0.917933 0.478987 0.814926
0.349460 0.534178 0.865541
ans(:,:,3,1) =
0.61806 0.40866 0.53618
0.19810 0.91036 0.25678
0.86147 0.41897 0.64443
0.72617 0.64882 0.61407
ans(:,:,4,1) =
0.55377 0.15132 0.43838
0.93128 0.99873 0.52454
0.88036 0.84050 0.81475
0.25184 0.85859 0.37180
ans(:,:,1,2) =
0.738389 0.860580 0.059313
0.062627 0.037361 0.691717
0.375035 0.761943 0.061768
0.714663 0.615794 0.324437
ans(:,:,2,2) =
0.146872 0.256419 0.368157
0.395067 0.540513 0.529821
0.407313 0.677987 0.673027
0.867863 0.035945 0.887424
ans(:,:,3,2) =
0.4906284 0.5851605 0.0413747
0.1563992 0.9161093 0.0191849
0.5943531 0.1002722 0.0900216
0.0021832 0.6841489 0.6641479
ans(:,:,4,2) =
0.7567010 0.1851823 0.9950826
0.6420206 0.0850503 0.3843941
0.3032742 0.6092447 0.0098233
0.7586690 0.8456620 0.4855678
ans(:,:,1,3) =
0.7764234 0.8102405 0.4518130
0.6454710 0.9681896 0.0082326
0.3859367 0.8468543 0.4195545
0.9851542 0.1570787 0.4728957
ans(:,:,2,3) =
0.389031 0.088541 0.171505
0.539026 0.942108 0.772355
0.471107 0.876273 0.109678
0.046125 0.323779 0.960741
ans(:,:,3,3) =
0.119634 0.626957 0.144026
0.379228 0.094830 0.838730
0.285164 0.054099 0.615673
0.625802 0.682348 0.782705
ans(:,:,4,3) =
0.0221458 0.3374686 0.6494100
0.6061537 0.2564040 0.4978930
0.8975514 0.4499792 0.2879290
0.0039387 0.1477363 0.6945299
>> len1 = 2; len2 = 3; len3 = 2; len4 = 2;