Finding Median

[mehwishobaid]

i dont know wat is wrong with my code. when i compile. i get the error

saying line 29: error: expression must have pointer-to-object type


#include <iostream>
using namespace std;
#include <vector>

double* median(double a[], int a_size) // Function Median
{ // Start of Function ( Median )
double* median;
int i,j;
double temp;
int numbers; // Variable Declared Median
if (a_size == 0) // Start of If Statement
return NULL; // if the size of the array is zero the pointer returns NULL


for (i = a_size-1; i >= 0; i--) //sorts out the array in an ascending order
{ // Start of For Loop
for (j = 1; j <= i; j++) // For Loop
{
if (a[j-1] > a[j]) // If Statement to Check the VAlue of A
{ // Start of IF Statement
temp = a[j-1]; // Assign Temp value to a
a[j-1] = a[j]; // Array in Descending Order
a[j] = temp; // Assign array to Temp
} // close of IF Statement
} // Close of For Loop
} // close of For in For Loop
//if the size is even number than takes the average else returns the middle number
if (a_size % 2 == 0) //compares the size for even number
median = ((numbers[a_size/2]) + (numbers[(a_size+1)/2])/2);// Define Median
else // else odd size
median = numbers[a_size+1]; // Assgin median for Odd Number of Array

return median; // Return Median value to Main
} // Close of Function ( Median )

int main() // Function main
{

int first;
int num2;
int i; // Variable Declared ( int )
int Exit; // Variable Declared ( Dummy )

cout << "Enter The Length of First vector"; // Output Statement for the Length of 1st Vector
cin >> first; // User Input for the Length of 1st Vector
cout<<endl; // Blank Line
vector <int> a(first); // Vector First


for (i=0; i<first; i++) // Start of For Loop for User Input 1st Vector
{
cout<< "Please enter element "<<i+1<<" of the First Vector";// Output For Entering Vector
cin>>num2; // User Input
cout<<endl; // Blank Line
a[i] = num2; // Adding Element in Vector A
}


cout <<"The Median of the Data is :" << median*(a, first) << "\n"; //Displays the Medianimum value out of the array
cout<<" Please Enter Any Key to Exit";
cin>>Exit;
return 0;
}

[Sick0Fant]

You have a thing or two to learn about pointer aritmetic. The ar[x] always returns a value, not an address (unless it's an array of addresses, which I doubt numbers is). You should try (ar + x)

[mehwishobaid]

if i try ( ar + x ) the line gives me the error of

expression must have (pointer-to-) function type
:S

i also need some help in callin the function Median.. when it says..
cout <<"The Median of the Data is :" << median*(a, first) << "\n";
the error associated with this cout statement is

error: expression must have arithmetic or enum type

[mehwishobaid]

thankyou for you help :).