Array Issue & Returning Functions - c++

Question

So I'm new to C++ and am writing a program to calculate the mean, median, standard deviation, min, and max of a program. The issues I'm having are that I don't know how to correctly call functions from other files in the project, and when I try to print(c out <<) my array, it returns a weird value like 0 x 0017 c 530 (disregard the spaces). If anyone could help me correctly return these functions, and print the list correctly, I would be very grateful! Here's my code (not including the .h file):
#include <iostream>
using namespace std;
#include "stats.h"
int main()
{
double nums[10000] = {};
int n;
cout << "Enter number of values: ";
cin >> n;
for (int i = 1; i <=n; i++) {
cout << "Enter number " << i << ": ";
cin >> nums[i-1];
}
// me trying to print the nu ms list
cout << nums << endl;
// me trying to call the function
double mean(double nums[], int n);
return 0;
}
stats. cpp
#include "stats.h"
double mean(double nums[], int n)
{
double sum = 0;
double average;
for (int i = 0; i > n; i++) {
sum += nums[i];
}
average = sum / n;
return average;
}

Answer 1

Instead of
cout << nums << endl;
Just like you have a loop to enter one value at a time in an array, you also need a similar loop to print one value at a time from the array.
To call a function from another translation unit, you would typically declare the function in a header file, your stats.h would be an excellent candidate:
double mean(double nums[], int n);
And then just invoke it from your main:
std::cout << mean(nums, n) << std::endl;
That's it.
Also:
using namespace std;
You need to have someone help you to get an amnesia, and completely forget that C++ has anything like this. This is bad programming practice.

Answer 2

double mean(double nums[], int n); is declaration of function, not invoking of function. You should
double mean_value = mean(nums, n);
cout << mean_value << endl;
And cout << nums << endl; won't print out the elements of the array, just the address of the array. You need to loop the array to print out all the elements.