Hello,

I'm trying to use numerical data that is in one column on an Excel spreadsheet for calculations of mean and standard deviation in C++. I have written a program that performs this same task but from a .txt file. Can anyone help me in the right direction? This is an assignment for an Intro to C++ class, and we can't have Excel calculate the mean or standard deviation and we can't convert the excel spreadsheet to .csv file. I've spent all week reading tutorials and forum posts and decided to ask the community directly. Thank You for any help!

Here is what I have for the mean and standard deviation from a .txt file...

Code:`#include <fstream>//using data from file stream`

#include <iostream>//allows user input and output

#include <cmath>//allows math functions

using namespace std;

void Read_Disk_File();//declares the void function "Read_Disk_File( )"

void Sum_and_Mean();//declares the void function "Sum_and_Mean( )"

void Standard_Dev();//declares the void function "Standard_Dev( )"

void Display_Results();//declares the void function "Display_Results( )"

int i, n;//integer

float sum, xx[1000];//variable 'sum' and 'xx', real numbers, 1000 spaces available for 'xx'

double mean = 0.0, sd = 0.0, a=0.0;

int main()

{

Read_Disk_File();//calls Read_Disk_File function

Sum_and_Mean();// calls Sum_and_Mean function

Standard_Dev();//calls Standard_Dev function

Display_Results();//calls Display_Results function

}

/***********************************************************************************************************

VOID FUNCTION Read_Disk_File

***********************************************************************************************************/

void Read_Disk_File()//defines the void function "Read_Disk_File( )"

{

ifstream xxx;//provides an interface to read data from files as input streams

xxx.open("MyData.txt");//opens a text file named "MyData.txt"

//===================================================================

i = 0;//assignment statement, assigns value of 0 to 'i'

while(!xxx.eof())//while not end of file, keep reading the file(somewhere at the end of the file there is a end of file marker)

{

xxx>>xx[i];

cout<<xx[i]<<endl;//prints to screen the array 'xx' as read from the .txt file

if(i>32000)//if the loop repeats more than 32000 times the cycle will break

break;//see above comment..

i++;

}

}

/***********************************************************************************************************

VOID FUNCTION Sum_and_Mean

***********************************************************************************************************/

void Sum_and_Mean()//defines the void function "Sum_and_Mean( )"

{

n=i-1;//gives 'n' a value

//calculates the sum

sum = 0;

for(i=0; i<=n-1; i++)

{

sum = sum + xx[i];//loops calculation 'i' times for the 'aNumber's entered by user (or sum += xx[i])

}

//calculates the mean

mean = sum/n;//calculates the mean

}

/***********************************************************************************************************

VOID FUNCTION Standard_Dev

***********************************************************************************************************/

void Standard_Dev()//defines the void function "Standard_Dev( )"

{

//calculates the standard deviation

a=0;

for(i=0; i<=n-1; i++)

{

a += pow((xx[i] - mean),2);//loops calculation 'n' times for the number of digits in the array

}

sd = sqrt( a/n );//calculates the square root of 'a' divided by the number of numbers

}

/***********************************************************************************************************

VOID FUNCTION Display_Results

***********************************************************************************************************/

void Display_Results()//defines the void function "Display_Results( )"

{

//displays the sum, mean, and standard deviation

cout<<"the sum is.. "<<sum<<endl;

cout<<"the mean is.. "<<mean<<endl;

cout<<"the standard deviation is.. "<< sd <<endl;//puts the standard deviation on the screen

system("pause");//pauses after display until user hits a key

}