need help finishing program!
i have the following program to figure the largest area of a triangle give a set of points. i have the class written to perform the needed mathematics but i am having some trouble getting it to work. can anyone help me!??? thank you
To compute the area of a triangle use the formula:
area = radical (s(s-a)(s-b)(s-c))
s - (a+b+c)/2
where and a, b, and c are the three sides of the triangle.
To calculate the length of the sides you can use the distance formula:
radical (x1-x2)^2+(y1+y2)^2
x1,x2 is one point
y1,y2 is the second point
where are the coordinates of one point and is the coodinates of the second point.
DATA
1. 0,0
2. 5,4
3. -7, -4
4. -2, 6
5. 4, -3
6. 1, 10
7. 0, -6
______________________________________
private void btnFindLargest_Click(object sender, System.EventArgs e)
{int i, j, k;
int iMax, jMax, kMax;
double [,] v = { {0,0},
{5,4},
{-7, -4},
{-2, 6},
{4, -3},
{1, 10},
{0, -6}
};
double maxArea, area = 0;
iMax = 0;jMax = 1;kMax = 2;
maxArea = FindArea(v, iMax, jMax, kMax);
for(i=0;i maxArea)
{iMax = i;
jMax = j;
kMax = k;
maxArea = area;
}
}
}
}
lstPoints.Items.Add("Maximum area is " + maxArea.ToString());
lstPoints.Items.Add("Vertex 1 is at " +
v[iMax,0].ToString() + ", " + v[iMax,1].ToString());
lstPoints.Items.Add("Vertex 2 is at " +
v[jMax,0].ToString() + ", " + v[jMax,1].ToString());
lstPoints.Items.Add("Vertex 3 is at " +
v[kMax,0].ToString() + ", " + v[kMax,1].ToString());
}
//
private double FindArea(double [,] v, int i, int j, int k)
{double a, b, c, s;
a = FindDistance(v, i, j);
b = FindDistance(v, i, k);
c = FindDistance(v, j, k);
s = (a + b + c)/2;
return Math.Sqrt(s*(s-a)*(s-b)*(s-c));
}
//
private double FindDistance(double [,]v, int x, int y)
{double x1, y1, x2, y2;
x1 = v[x,0]; y1 = v[x,1];
x2 = v[y,0]; y2 = v[y,1];
return Math.Sqrt((x1-x2)*(x1-x2) + (y1-y2)*(y1-y2));
}