There are reasons unrelated to pointer implementations such as the interval argument from Dijkstra's article or conversions between flat and multidimensional ar

There are reasons unrelated to pointer implementations such as the interval argument from Dijkstra's article or conversions between flat and multidimensional array indexes. There's a reason why most mathematical sequences start at zero: it leads to simpler expressions. Vec (and especially matrix) indexing should have been zero-based.