# File lib/backports/1.9.2/stdlib/matrix.rb, line 298 def initialize(rows, column_size = rows[0].size) # No checking is done at this point. rows must be an Array of Arrays. # column_size must be the size of the first row, if there is one, # otherwise it *must* be specified and can be any integer >= 0 @rows = rows @column_size = column_size end