rfgrgf, stupid pointers

yes, this is another pointer question

ok, here's my code:

Code:

#include <iostream.h>
#include <math.h>  //edit, forgot to add this :)

void ModifyPointer(double* value, bool*ok)  // forgot the void, too
{
value=sin(45);
ok=true;
}

void main()
{
double temp1;
bool temp2;

ModifyPointer(&temp1,&temp2);
cout << temp1 << " is " << temp2 << endl;
}

now, theoretically, that would make it so that temp1 and temp2 are equal to sin of 45 and true (respectively). Thing is, when I try and compile this, it returns an error:

error C2440: '=' : cannot convert from 'double' to 'double *'

and that ONLY happens for the sin one, it doesn't happen for the bool one. Now, i've tried MANY things (from reinterprets, to just plain (double *), and none of the options i've tried so far have worked....)

so i need to know why this isn't working, and how i can fix it.

NOTE: the above isn't my actual code, it's just pseudo code in case you haven't noticed, but it should compile and generate the error i think

thanks in advance.

ok, i'm stupid, rgfgrfggrgf

found out that because i was using this in a switch statement that for some reason it wouldn't work right.........

so i just made them equal temp variables, and when i got out of the switch, just assigned the temp vars to the pointers, and now it works

but now, i'm trying to assign them as such:

*ok=temp;

but when i assign the value, the program crashes (lol), now i'm really confused

screw it, i'm just going to make the variables global (as much as i don't want to) but C++ is really pi$$ing me off right now

so if anyone figures this out, just reply here, but otherwise, i'm moving on

Dear oh dear the error tells you what you are doing. maybe you should read the faq pointers article.
You are assigning a double to a pointer to a double.

value=sin(45);

lets look at the types

double* = double;

see the problem?

The faq pointer tut will fix it for you.

After reading the tutorial on pointers note that there is another way to do this: using references. Next, use int main (void main?????). Oh yea, use the newer headers.

Code:

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

void ModifyPointer(double &value, bool &ok)
{
   value = sin(45);
   ok = true;
}

int main()
{
   double temp1 = 0;
   bool temp2 = false;

   ModifyPointer(temp1, temp2);
   cout << temp1 << " is " << temp2 << endl;

   return 0;
}

Originally posted by jverkoey
but now, i'm trying to assign them as such:

*ok=temp;

but when i assign the value, the program crashes (lol), now i'm really confused

Thats because the ok pointer is probably invalid as in you never set it to anything useful. A "crazy pointer."