Matrix as a list of the matrix row prolog

Question

I have to representing a matrix as a list of the matrix rows with the term like this [[a,b],[c,d]] with representing numbers in Peano notation.

I have to obtain a row of matrix

ow(X,N,C): C is the N-th row of matrix X. and the column of matrix

column(X,N,C): C es the N-th column of matrix X.

alse this One to decompose a matrix in its first column and the rest of the matrix (which is exactly the same matrix but without the first column):

first_column(X,C,R): matrix X is formed by a first column C in
                     front of matrix R. 

Could somebody help me?

Answer 1

Peano' notation simplifies expressing recursive algorithms. I assume matrix indexing is 0 based, and will show you how to get the simplest task of your assignment.

row([Row|_], 0, Row).
row([_|Rows], succ(N), Row) :- row(Rows, N, Row).

test (get the second row, with index 1):

?- row([[a,b], [c,d]], succ(0), R).
R = [c, d] ;
false.

This shows the essential ingredients you'll use to answer the other two tasks.