How to get row and column length of a 2-dimensional array in rails 3?
can somebody tell how to get the row and column length of a 2-dimensional array in rails 3?
My array goes like this:
payroll = Array.new[Payroll.count][2]
When we are getting the length of a 1-dimensional array we do like
array.lengthHow about in a 2-dimensional array?
Im thinking of doing something like开发者_StackOverflow中文版:
payroll = Array.new[Payroll.count][2]
for i in 0..payroll.row.length - 1
for j in 0..1
puts payroll[i][j]
end
end
I just wanna know the right way. Pls help...
A two dimensional array is just an array of arrays, so just use payroll.length
to get the height and payroll[0].length
to get the width (assuming all rows are the same width). Here's what your loop looks like using that idea:
for i in 0..payroll.length - 1
for j in 0..payroll[i].length - 1
puts payroll[i][j]
end
end
But an easier way to loop through an array is using an iterator method. Here I'll change the for
loops to each.with_index
(use each_with_index
if your Ruby doesn't support each.with_index
):
payroll.each.with_index do |row, i|
row.each.with_index do |cell, j|
puts payroll[i][j]
end
end
And now I'll make it even simpler since I'm assuming you don't really need access to the indexes at all, just the individual elements in the array:
payroll.each do |row|
row.each do |cell|
puts cell
end
end
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