Subj : Re: Any help on why?
To   : borland.public.cpp.borlandcpp
From : Stan DeGroff
Date : Wed Jul 07 2004 03:53 am

> >... by putting in some printf statements to aid in debug, That prints the
> >variable "xresult" resulted in printing 0x0000. However the variable
> >"result" printed ok.
>
> Wrong type specifier in the printf().
> >      printf("%d  %X, %X\n", i, xresult, result);
>
> %X is used with integers. Use %f with doubles.

Wayne,
I wanted to look at the data as a Hexadecimal floating pt. number.  It
didn't effect it when I tried %f.
"result" worked ok with %X.  "xresult" returned 0 in either format.  No
particular reason.

>
> Did you type this in or copy & paste? This line looks odd:
> >      xresult = double va_arg(arglist, double);
> It should be a typecast:
> xresult = (double) va_arg(arglist, double);
>


The original text for the function was :
-----------
double AddDouble(int x, ...)
{
     va_list arglist;
     int i;
    double result = 0.0;

   printf("The number of arguments is : %d\n", x);
   va_start(arglist, x);
   for (i=0; i<x; i++)
        result += va_arg(arglist, double);
   va_end(arglist);
   return result;
-----------------------

I didn't get the format right for type cast.  Still not sure what, when or
how with type cast.
I was trying anything to find out what works.  Trying to type it as a double
was one of my experiments.
Is that what I need to do to get xresult to print?


Here's what the output was (type cast or not, same output):
------------
GIven an argument: 1.5
The number of arguments is : 1
0  0, 3FF80000
The result returned bu AddDouble() is: 1.5

Given arguments: 1.5 and 2.5
The number of arguments is : 2
0  0, 3FF80000
1  0, 40040000
The result returned by AddDouble() is 4.0

Given arguments: 1.5, 2.5 and 3.5
The number of arguments is : 3
0  0, 3FF80000
1  0, 40040000
2  0, 400C0000
The result returned by AddDouble() is 7.5

Given arguments: 1.5, 2.5, 3.5 and 4.5
The number of arguments is : 4
0  0, 3FF80000
1  0, 40040000
2  0, 400C0000
3  0, 40120000
The result returned by AddDouble() is 12.0

--------------------

I think when I figure out why xresult doesn't print, I will have hit another
milestone in my understanding of how C works.


>
> --
> Wayne A. King
> (waking@idirect.com, Wayne_A_King@compuserve.com)

.