Rows vs Columns
In this book we use the following convention for 2D arrays: “row” refers to the first index of the array and “column” refers to the second. So for a 2D array A, A(i,j) is the element in row i and column j. The PM command makes this easy to visualize:
a = INTARR( 4, 8 )    &    a(2,5) = 1    &    PM, a
 
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