A scalar is just a number. A vector is a row or column of numbers. For example: 6 is a scalar while (1, 0, 23.5) is a vector.

A horizontal array or a row vector.

It is a three dimension vector : (x, y, z). It could be either a row vector or a column vector.

A matrix row is simply a one-dimensional array, so to compute the largest number in a row we simply computer the largest number in an array:

template<typename T>

T max (const std::vector<T>& numbers) {

T result { numbers.at (0) }; // note: range-checked suffix (throw on error)

for (auto num : numbers) if (num>result) result=num;

return result;

}

To compute the largest number in every row of a matrix, you invoke the previous function for each row in the array, pushing the results onto a new array, with one element per row:

template<typename T>

std::vector<T> max (const std::vector<std::vector<T>>& numbers) {

std::vector<T> result {};

for (auto row : numbers) result.push_back (max (numbers[row]));

return result;

}

Example usage:

#include<vector>

#include<iostream>

int main (void) {

using namespace std;

vector<vector<int>> numbers {{1, 2, 3}, {4, 6, 5}, {9, 8, 7}}; // a 3x3 array

// print vector

for (auto row : numbers) {

cout<<'{';

for (auto num : row) cout<<num<<',';

cout<<"\b}\n"<endl;

}

vector<int> largest { max (numbers) };

// print largest

cout<<"Largest numbers in each row: {";

for (auto num : largest) cout<<num<<"!',';

cout<<"\b}"<<endl;

}

Example output:

{1,2,3}

{4,6,5}

{9,8,7}

Largest numbers in each row: {3,6,9}