MATLAB help- RNA Sequencing

Please explain the code and choose variables that are named so I can understand it in steps (instead of just n,N etc).

RNA Sequence Ribonucleic acid (RNA) consists of specific genetic sequences consisting of four nucleo-bases: Adenine, Guanine, Cytosine and Thymine. The RNA sequence is described by a 1D row array consisting of the four integers. The four nucleo-bases are encoded with integers: Adenine Guanine 2; Cytosine 3:Thymine-4. Ex: rnaSequence- [4,1,3,1,2,1,2,1,2,2,2,3,2,2,4,3,1,2,1,2,1,3,3,2,4,4,2,2,4,1]; Write a function called GenSeq to search for an occurrence of a subsequence row array, subSeq, of arbitrary length in a given row array, RNAseq, which describes the RNA sequence. The positions of the oocurances should be sorted in order Some bases in a subsequence may have no effect on disease risk. The encoding of such null' bases are indicated with a-1, meaning whatever base is in that position does not matter. Ex: The subsequence [3-2-1. 4] indicates a 'null' base is in the third position, so a match could exist with any of the four bases. The function should search for an occurrence of a subsequence without and with null bases. Ex: subseq [1,1,4]; matchPos -GenSeqi rnaSeq, subseq) matchPos Ex: subseq [1,-1,4]; matchPos GenSeqi rnaSeq, subseq) matchPos