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Obvious answer...that's why its showing Junk characters in the english OS. 
modified 31-Jul-14 6:04am.
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Can someone point me to some C++ or C# examples on how to loop thru a group of similar CSV files and import them to an access db? Thanks.
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Hi,
I am working on a project which requires to use a web service in C++ native application. I have searched on the net and found many links which explains that it is possible using C++ REST SDK. I have downloaded and installed the C++ REST SDK for visual studio 2010 but couldn't find any sample application using REST SDK to call a web service.
Can anyone help me regarding this. How to use a web service in C++ using REST SDK.
Regards,
mba
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I have recently written a 'project browser' ctrl for my hobby ide BUT when i right click on an item to 'select item and show menu' even though the carat is on the new item the control reports the active TREEVIEWITEM is the previously selected item and the menu acts on the prev selected item.
With listboxes its easy you just subclass the ctrl and simulate "press lmb down and lmb up" when rmb is pressed but this method doesnt work at all with treeviews.
How do i select a item with the rmb?
Ps. you can be technical with your responce, im v.familiar w/ winapi.
thx bob
Sorry guys lol. Just solved it. You use the TVM_HITTEST to get the current item under the mouse cursor then call TVM_SELECTITEM w/ that item.
Then call trackpopupmenu as normal.
4 hours wasted last night on that one... still happy ending. 
modified 30-Jul-14 6:30am.
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What messages or notifications are you responding to?
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#include<stdio.h>
#include<stdlib.h>
#include<math.h>
float summation(float g);
int main(int argc,int *argv[])
{
srand(12345);
float z;
float a=0.2,y=0.0;
int i;
for(i=0;i<5;i++)
{
float b=((float)rand()/(float)(RAND_MAX))*a;
printf("%f\n",b);
z=summation(b);
}
printf("summation:\n%f\n",z);
return 0;
}
float summation(float g)
{
int i;
float y[5],sum =0.0;
float c=0.0;
for(i=1;i<5;i++)
{
float z=y[i]-c;
float t = sum+z;
c=(t-sum)-z;
sum=t;
return sum;
}
}
output
0.035679
0.079935
0.033320
0.042424
0.012387
summation:
0.000000 
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Your summation function makes no sense. You pass in a parameter which is ignored and then do some fairly random calculations, and return the value which will be zero, after a single iteration of the loop.
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so as far as u say which way i should proceed?
actually my logic was not working so was planning to implement kahan summation.
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maibam debina wrote: so as far as u say which way i should proceed?
Well the first thing you need to do is to define what the summation function is supposed to do; I cannot make any sense out of it. Once you have done that, then define the steps required and convert them to code. It would probably help you immensely to use meaningful names for your variables rather than single letters which make it difficult to understand.
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can u please help me out with code...
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Well I could, but i) I have no idea what your summation function is supposed to do, and ii) you would learn more by trying it yourself.
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Actually the logic which i use to implement for performing the summation was
<blockquote class="quote"><div class="op">Quote:</div>for(i=0;i<5;i++)
{
float f= ((float)rand()/(float)(RAND_MAX))*a;
y=square(f);
sum +=y;
}
printf("\n Summation Of Square Number is:=%f\t\n",sum); </blockquote>
but it doesnot seem well its not giving the exact summation value,all i want was to perform summation of the generated float random numbers .
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Are you sure that sum contains zero at the beginning of the loop? In the statement:
float f= ((float)rand()/(float)(RAND_MAX))*a;
what is the value of a?
And since you are not printing any of the intervening values, how can you be sure the final sum is not correct?
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for(i=0;i<5;i++)
{
float f= ((float)rand()/(float)(RAND_MAX))*a;
printf("%f\t",f);
y=square(f);
printf("\t\t%f\n",y);
}
for(i=0;i<5;i++)
{
float f= ((float)rand()/(float)(RAND_MAX))*a;
y=square(f);
sum +=y;
}
printf("\n Summation Of Square Number is:=%f\t\n",sum);
i have print at the 1st for loop...
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And in the second loop you will have a different set of numbers, as returned by the calls to rand(). I also cannot find a reference to square, is this another function in your code?
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ya it is thank fren i got it...matter was with the printf statement i gav at second loop ,wen i pass the printf statement inside the 1st loop itself n removing the second for loop as condition where same ...den i got the exact answer..
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 What are you doing?
OK, you are trying to implement the "Kahan summation algorithm"[^].
However you have to read carefully and understand it, before actually coding.
For instance, as shown by the algorithm pseudo-code[^], the parameter to the summation function must be an array, while you are using a float.
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?!
-- C++ FQA Lite
modified 30-Jul-14 4:20am.
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i tried using array but seem it not working can u please help me out with code making modification...actual thing what i want is to do the summation of all the generated random number which is store at b.
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#include <stdio.h>
#define N 5
double summation(double g[], int size);
int main()
{
double a[N] =
{
0.035679,
0.079935,
0.033320,
0.042424,
0.012387
};
double s[N];
int i;
for (i=0; i<N; ++i)
{
s[i] = a[i]*a[i];
}
printf("summation = %g\n", summation(s,N));
}
double summation(double g[], int size)
{
int i;
double sum =0.0;
double c=0.0;
for(i=0; i<size ;i++)
{
double y = g[i] -c;
double t = sum + y;
c = (t-sum) - y;
sum = t;
}
return sum;
}
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?!
-- C++ FQA Lite
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Consider the following implementation of a summation function and various ways of creating/populating an array for it to work on.
1. static data declared at compile time
2. dynamic data allocated with the c function malloc
3. dynamic data allocated with the c++ operator new
#include <cstdlib>
#include <cstdio>
float sumArrayElements(float array[], int numItems)
{
int i;
float result = 0;
for (i=0; i<numItems; i++)
result += array[i];
return result;
}
int main ()
{
float array1[5] = {10.2, 13.7, 14.8, 99.0, 0.0};
float arraySum1 = sumArrayElements( array1, 5);
printf("Array sum: %.2f\n",arraySum1);
int i;
float *array2;
int dynamicCount1 = 5;
array2 = (float*)malloc(dynamicCount1 * sizeof(float) );
for (i=0; i<dynamicCount1; i++)
array2[i] = (float)rand()/(float)(RAND_MAX);
float arraySum2 = sumArrayElements( array2, dynamicCount1);
free(array2);
printf("Array sum: %.2f\n",arraySum2);
int dynamicCount2 = 10;
float *array3 = new float[dynamicCount2];
for (i=0; i<dynamicCount2; i++)
array3[i] = (float)rand()/(float)(RAND_MAX);
for (i=0; i<dynamicCount1; i++)
array3[i] = (float)rand()/(float)(RAND_MAX);
float arraySum3 = sumArrayElements( array3, dynamicCount2);
delete array3;
printf("Array sum: %.2f\n",arraySum3);
return 0;
}
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thanks for your contribution but this is the logic i apllied for summation 'result +=array[i]' but this is giving the approximate answer not the exact one.
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Except for a rather small subset of numbers, calculations with computers involving floating-point numbers are approximate.
Integer arithmetic doesn't suffer from this pitfall.
However, if you are talking about the result of the code I posted - then consider reviewing the printf statements - in each of them I have used the %.2f format specifier to tell printf to only print 2 digits after the decimal place. The point is - the answer is as close to exact as floats will give you, it is only the display that is (grossly) approximate.
You can get a less approximate result printed if you change the print specifiers to %f
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