Exercise 3: Sum the Rows of a Matrix

Write code that calculates the array produced by summing the entries of each row of a matrix.

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Problem statement

In this exercise, you’re given a nested array. Sum the entries in each row of the matrix and return an array containing these sums.

Example

For example, consider the following array:

nested_array = [
  [1, 2, 3],
  [4, 5, 6],
  [7, 8, 9]
]

We get the following output in return:

[6, 15, 24]

Try it yourself

def sum_the_cols(nested_array)
  result = []
  # Start your code here
 
  return result
end

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