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Floating point exception

enterprize (15)
My compiler, XCode, gave me the message "Floating point exception," after going through the my code below, then ended the program abruptly.

It goes through other ones that use + instead of - fine, and also runs the one where both +'s and -'s are reversed.

Here is the relevant code (this is the only part that differs from the working code, and is thus the erroneous part)

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if ((double ((newx-oldx)/(newy-oldy)))==-1 && (newx-oldx)>0)
	direction=2;

if (direction == 2)
{
	for (int t = 0; t<newx-oldx; t++)
	{
		if(!(!(FindColor(oldx+t, oldy-t)==' ')))
		{
			test=true;
			break;
		}
		if (test)
			break;
	}
	if (test)
		break;
	if (!(FindColor(newx, newy)==CharTurn(WTurn)))
		ValidMove=true;
}


This is as compared to the below, which definitely works.

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if ((double((newx-oldx)/(newy-oldy)))==1 && (newx-oldx)>0)
	direction=1;

if (direction == 1)
{
	for (int t = 0; t<newx-oldx; t++)
	{
		if(!(!(FindColor(oldx+t, oldy+t)==' ')))
		{
			test=true;
			break;
		}
		if (test)
			break;
	}
	if (test)
		break;
	if (!(FindColor(newx, newy)==CharTurn(Wturn)))
		ValidMove=true;
}




the slope I used was definitely -1 for
double ((newx-oldx)/(newy-oldy)))==-1
so I don't see what the problem is, unless double is unsigned for some reason.

Sorry if my question is unclear, because I am not including all of the code.
Really, my question was just what "Floating point exception" means, and if any of my code would lead to that error.

Thanks.
Last edited on
enterprize (15)
It works now at that point, but now fails at 
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if (direction == 2)
{
	for (int t = 0; t<newx-oldx; t++)
	{
		if(!(!(FindColor(oldx+t, oldy-t)==' '))) //here down
		{
			test=true;
			break;
		}
		if (test)
			break;
	}
	if (test)
		break;
	if (!(FindColor(newx, newy)==CharTurn(Wturn)))//to here
		ValidMove=true;
}


Because if FindColor(oldx+t, oldy-t) is not the space character, it gives that error.
Last edited on
Bazzy (6281)
What's in FindColor?
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