Expression-must-have-pointer-to-object-type

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  1. #1
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    Expression-must-have-pointer-to-object-type

    What does the above error mean? I have typdef Coeffs as double and I'm trying to use it in func1
    Line 18: Poly --> expression must have pointer to object type


    Code:
    typedef double Coeffs;
    
    int main()
    {
    	Coeffs Poly;
    
    	...
    }
    
    func1(Coeffs Poly, int num_verts, double*coeff)
    {
    	double A, B, C, D;
    	int i, j;
    	A = B = C = D = 0;
    	for(i=0;i<num_verts;i++)
    	{
    		j = (i+1) % num_verts;
    		A += ((Poly[j][1] - Poly[i][1]) * (Poly[i][2] + Poly[j][2]));
    		B += ((Poly[j][2] - Poly[i][2]) * (Poly[i][0] + Poly[j][0]));
    		C += ((Poly[j][0] - Poly[i][0]) * (Poly[i][1] + Poly[j][1]));
    	}
    }

  2. #2
    C++ Witch laserlight's Avatar
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    In func1, Poly is a Coeffs, therefore Poly is a double, hence Poly[j][1] does not make sense.
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
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