Thread: Question about a certain code with the C++ syntax

I will play along with that. Now a seperate issue for Jim.

Code:

for (index==0; index<numberofterms; index++)
{   
    cout<<"Enter temperature you want to input in Celsius"<<(index+1);
    cout<<": ";
    cin>>temperature[index];
    temperature(numberofterms).push_back(temperature[index])

Would this be an appropriate use of the push back function?

Also another question is when I tried running my code, it does the first part and then it doesnt complete the rest of the code. It must be an error with the code correct? Even though the complier hasnt detected anything wrong.

Even though the complier hasnt detected anything wrong.

Just because the compiler doesn't detect an error doesn't mean your program is correct.

Also another question is when I tried running my code, it does the first part and then it doesnt complete the rest of the code.

Run your program through your debugger. Your debugger will tell you exactly where it detected the error and you will be able to examine your variables at the time of the crash. Then you should be able to determine what variable is incorrect and back trace until you find the actual problem.

Jim

Fixed the problem I think.

//Running Mean for 3 points with even weights


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




int main ()


{
float numberofterms;
float number_of_elements_avg;
vector<float> temperature; //Define a vector of 5 floats
vector<float> movingavg;
int index; //Loop counter

cout<<"Enter the number of terms you want: " <<endl;
cin>>numberofterms;
cout<<"Enter how many pt average you would like to take: "<<endl;
cin>>number_of_elements_avg;


for (index==0; index<numberofterms; index++)
{
float average;

cout<<"Enter temperature you want to input in Celsius"<<(index+1);
cout<<": ";
cin>>temperature[index];
temperature.push_back(temperature[index]);

if (index==0)
{ movingavg[index]=temperature[index];
cout<<"Temperature [1]= "<<temperature[0]<<" C"<<endl;
continue;
}
else if (index==numberofterms-1)
{
movingavg[index]=temperature[index];
cout<<"Temperature ["<<numberofterms<<"]= "<<temperature[numberofterms-1]<<" C"<<endl;
continue;
}
for (int index =0; numberofterms-number_of_elements_avg; index++);
{
average = accumulate(temperature.begin() + index - number_of_elements_avg/2, temperature.begin() + index + number_of_elements_avg/2 + 1, 0) / (number_of_elements_avg + 1);
}
//average= (temperature[index-1]+temperature[index]+temperature[index+1]/3);
//movingavg[index]=average;
cout<<"Temperature ["<<index+1<<"] = "<<average<<" C"<<endl;
cout<<"The original temperature ["<< index+1<<"]"<<temperature[index]<<"] C has been replaced." <<endl;
}






system ("PAUSE");


return 0;


}

PROBLEM: Instainted from here. What kind of error is that?

Originally Posted by Elysia

Add code tags, indent code, give the real (full) compile errors.

CODE ERROR:
Line 46: C:\Users\.... Message: Instantiated from here. That's the line in the average part.

Originally Posted by Elysia

That's not the full error. I repeat the above:
Add code tags, indent code, give the real (full) compile errors.
Copy everything. All the output.

Let me attempt what you are trying to ask.

My Code:

Code:

//Running Mean for 3 points with even weights

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




int main ()


{
float numberofterms;
float number_of_elements_avg;  
vector<float> temperature; //Define a vector of 5 floats
vector<float> movingavg;
int index; //Loop counter
 
cout<<"Enter the number of terms you want: " <<endl;
cin>>numberofterms; 
cout<<"Enter how many pt average you would like to take: "<<endl;
cin>>number_of_elements_avg;


for (index==0; index<numberofterms; index++)
{   
    float average;
    
    cout<<"Enter temperature you want to input in Celsius"<<(index+1);
    cout<<": ";
    cin>>temperature[index];
    temperature.push_back(temperature[index]);
     
     if (index==0)
     { movingavg[index]=temperature[index];
       cout<<"Temperature [1]= "<<temperature[0]<<" C"<<endl;
       continue;
     }
     else if (index==numberofterms-1)
     {
     movingavg[index]=temperature[index];
     cout<<"Temperature ["<<numberofterms<<"]= "<<temperature[numberofterms-1]<<" C"<<endl;
     continue;
     }
       for (int index =0; numberofterms-number_of_elements_avg; index++); 
         {
         average = accumulate(temperature.begin() + index - number_of_elements_avg/2, temperature.begin() + index + number_of_elements_avg/2 + 1, 0) / (number_of_elements_avg + 1);
         }
        //average= (temperature[index-1]+temperature[index]+temperature[index+1]/3);
        //movingavg[index]=average;
    cout<<"Temperature ["<<index+1<<"] = "<<average<<" C"<<endl;
    cout<<"The original temperature ["<< index+1<<"]"<<temperature[index]<<"] C has been replaced." <<endl;
}






system ("PAUSE");


return 0;


}

Compiler Error Message from C++ Bloodshead:

Compiler: Default compiler
Executing g++.exe...
g++.exe "C:\Users\FutureNWS4caster\Desktop\C++ Revised.cpp" -o "C:\Users\FutureNWS4caster\Desktop\C++ Revised.exe" -g3 -I"C:\Dev-Cpp\lib\gcc\mingw32\3.4.2\include" -I"C:\Dev-Cpp\include\c++\3.4.2\backward" -I"C:\Dev-Cpp\include\c++\3.4.2\mingw32" -I"C:\Dev-Cpp\include\c++\3.4.2" -I"C:\Dev-Cpp\include" -L"C:\Dev-Cpp\lib" -g3
C:\Users\FutureNWS4caster\Desktop\C++ Revised.cpp: In function `int main()':
C:\Users\FutureNWS4caster\Desktop\C++ Revised.cpp:41: warning: passing `float' for converting 1 of `typename _Alloc::reference std::vector<_Tp, _Alloc>:perator[](size_t) [with _Tp = float, _Alloc = std::allocator<float>]'


C:\Users\FutureNWS4caster\Desktop\C++ Revised.cpp:46: warning: name lookup of `index' changed


C:\Users\FutureNWS4caster\Desktop\C++ Revised.cpp:17: warning: matches this `index' under ISO standard rules


C:\Users\FutureNWS4caster\Desktop\C++ Revised.cpp:44: warning: matches this `index' under old rules
C:\Users\FutureNWS4caster\Desktop\C++ Revised.cpp:46: warning: passing `float' for converting 1 of `__gnu_cxx::__normal_iterator<_Iterator, _Container> __gnu_cxx::__normal_iterator<_Iterator, _Container>:perator-(const typename std::iterator_traits<_Iterator>::difference_type&) const [with _Iterator = float*, _Container = std::vector<float, std::allocator<float> >]'
C:\Users\FutureNWS4caster\Desktop\C++ Revised.cpp:46: warning: passing `float' for converting 1 of `__gnu_cxx::__normal_iterator<_Iterator, _Container> __gnu_cxx::__normal_iterator<_Iterator, _Container>:perator+(const typename std::iterator_traits<_Iterator>::difference_type&) const [with _Iterator = float*, _Container = std::vector<float, std::allocator<float> >]'


C:/Dev-Cpp/include/c++/3.4.2/bits/stl_numeric.h: In function `_Tp std::accumulate(_InputIterator, _InputIterator, _Tp) [with _InputIterator = __gnu_cxx::__normal_iterator<float*, std::vector<float, std::allocator<float> > >, _Tp = int]':
C:\Users\FutureNWS4caster\Desktop\C++ Revised.cpp:46: instantiated from here
C:/Dev-Cpp/include/c++/3.4.2/bits/stl_numeric.h:89: warning: converting to `int' from `float'


Execution terminated

Not working for some reason. All the errors are gone but they are just two errors. Strange???

Ok I download visual Studio C++. But somehow its not working even those the only errors per say I am getting is Warning.

Code:

//Running Mean for 3 points with even weights
 
#include "stdafx.h"
#include <iostream>
#include <iomanip>
#include <vector>
#include <numeric>
using namespace std;
 
int main ()
{
    int numberofterms;
    float number_of_elements_avg; 
    float tempstorage;
    vector<float> temperature; //Define a vector of 5 floats
    vector<float> movingavg;
    int i; //Loop counter
 
    cout<<"Enter the number of terms you want: " <<endl;
    cin>>numberofterms;
    cout<<"Enter how many pt average you would like to take: "<<endl;
    cin>>number_of_elements_avg;
 
 
    for (i=0; i<numberofterms; i++)
    {  
        float average;
 
        cout<<"Enter temperature you want to input in Celsius"<<(i+1);
        cout<<": ";
        cin>>tempstorage;
        temperature.push_back(tempstorage);
 
        if (i=0)
        {
            movingavg[i]=temperature[i];
            cout<<"Temperature [1]= "<<temperature[0]<<" C"<<endl;
            continue;
        }
        else if (i=numberofterms-1)
        {
            movingavg[i]=temperature[i];
            cout<<"Temperature ["<<numberofterms<<"]= "<<temperature[numberofterms-1]<<" C"<<endl;
            continue;
        }
        for (int j=0; j<numberofterms-number_of_elements_avg; j++)
        {
            average = accumulate(temperature.begin() + j - number_of_elements_avg/2, temperature.begin() + j + number_of_elements_avg/2 + 1, 0) / (number_of_elements_avg + 1);
        }
        //NOT PART OF THE CODE average= (temperature[index-1]+temperature[index]+temperature[index+1]/3);
        //NOT PART OF THE CODE movingavg[index]=average;
        cout<<"Temperature ["<<i<<"] = "<<average<<" C"<<endl;
        cout<<"The original temperature ["<< i+1<<"]"<<tempstorage<<"] C has been replaced." <<endl;
    }
 
    system ("PAUSE");
    return 0;
}

OUTPUT:

1>------ Build started: Project: RunningMean, Configuration: Debug Win32 ------1> RunningMean.cpp
1>c:\users\futurenws4caster\documents\visual studio 2010\projects\runningmean\runningmean\RunningMean. h(48): warning C4244: 'argument' : conversion from 'float' to '__w64 int', possible loss of data
1>c:\users\futurenws4caster\documents\visual studio 2010\projects\runningmean\runningmean\RunningMean. h(48): warning C4244: 'argument' : conversion from 'float' to '__w64 int', possible loss of data
1> .NETFramework,Version=v4.0.AssemblyAttributes.cpp
1> RunningMean.vcxproj -> c:\users\futurenws4caster\documents\visual studio 2010\Projects\RunningMean\Debug\RunningMean.dll
========== Build: 1 succeeded, 0 failed, 0 up-to-date, 0 skipped ==========

Try using a floating point number for the third argument of the accumulate call. For zero try 0.0.

Jim

Originally Posted by jimblumberg

Try using a floating point number for the third argument of the accumulate call. For zero try 0.0.

Jim

If I understood correctly

Code:

for (int j=0; j<numberofterms-number_of_elements_avg; j++)
        {
            average = accumulate(temperature.begin() + j - number_of_elements_avg/2.0, temperature.begin() + j + number_of_elements_avg/2.0 + 1.0, 0.0) / (number_of_elements_avg + 1.0);
        }

Do I need to change to the bold? Not only the 0.0 as well?

Originally Posted by jimblumberg

Try using a floating point number for the third argument of the accumulate call. For zero try 0.0.

Jim

If I understood correctly

Code:

for (int j=0; j<numberofterms-number_of_elements_avg; j++)
        {
            average = accumulate(temperature.begin() + j - number_of_elements_avg/2.0, temperature.begin() + j + number_of_elements_avg/2.0 + 1.0, 0.0) / (number_of_elements_avg + 1.0);
        }

Still showing this as a warning. This part of the code I think is the only problem.

1>------ Build started: Project: RunningMean, Configuration: Debug Win32 ------
1> RunningMean.cpp
1>c:\users\futurenws4caster\documents\visual studio 2010\projects\runningmean\runningmean\RunningMean. h(48): warning C4244: 'argument' : conversion from 'float' to '__w64 int', possible loss of data
1>c:\users\futurenws4caster\documents\visual studio 2010\projects\runningmean\runningmean\RunningMean. h(48): warning C4244: 'argument' : conversion from 'float' to '__w64 int', possible loss of data
1>c:\users\futurenws4caster\documents\visual studio 2010\projects\runningmean\runningmean\RunningMean. h(48): warning C4244: '=' : conversion from 'double' to 'float', possible loss of data
1> RunningMean.vcxproj -> c:\users\futurenws4caster\documents\visual studio 2010\Projects\RunningMean\Debug\RunningMean.dll
========== Build: 1 succeeded, 0 failed, 0 up-to-date, 0 skipped ==========
Do I need to change to the bold? Not only the 0.0 as well?

No you only need to change the last parameter. The other items must be integers because they are being used as indexes. I would also recommend you do all the calculations separately and then just plug in a variable into your accumulate function. For example instead of using this calculation inside the accumulation function I would assign it to a variable.

Code:

// j - number_of_elements_avg/2.0 
unsigned int start = j - number_of_elements_avg/2;
average = accumulate(temperature.begin() + start, t ......

You should also check and insure that j is larger than the negative calculation. Remember start can't be negative, and it shouldn't be larger than your vector size.

Jim

Originally Posted by jimblumberg

No you only need to change the last parameter. The other items must be integers because they are being used as indexes. I would also recommend you do all the calculations separately and then just plug in a variable into your accumulate function. For example instead of using this calculation inside the accumulation function I would assign it to a variable.

Code:

// j - number_of_elements_avg/2.0 
unsigned int start = j - number_of_elements_avg/2;
average = accumulate(temperature.begin() + start, t ......

You should also check and insure that j is larger than the negative calculation. Remember start can't be negative, and it shouldn't be larger than your vector size.

Jim

I see break up the parts to find the source of the problem.