Suggestions for rewrite of Matrix library

[dcuny]

There are a couple of Lua idioms that you might want to take advantage of for the Matrix library.

First, you can get the count of elements in a table t with the # operator.

So to get the count of rows in a table, you can write:

local rows = #t

Similarly, you can get the count of columns in the table by getting the count from the first row:

local cols = #t[1]

So instead of storing the rows and columns, you could write:

-- get the number of rows and columns
local rows, cols = #m1, #m1[1]

If you're going to be iterating over a 2 dimensional table, it's a bit faster to place the row in a variable. You can then index into the row with row[j], which is slightly faster (but perhaps less easy to read).

For example, instead of:

for i = 1, rows do
  for j = 1, cols do
    foo( t[i][j] )
  end
end

You can use the ipairs iterator, which returns the index and value from the table:

for i, row in ipairs( t ) do
  for j, col in ipairs( row ) do
    foo( col )
  end
end

On the other hand this sort of idiom can make the code harder to read.

Here's a rewrite of the Matrix library using those idoms: Matrix.txt

I'm not saying that it's any better than what you wrote, it's just something to consider.