Question

I am required to create a program which reads in data from a .cvs file, and use these (x, y and z) values for a series of calculations.

I read in the file as a string, and then split this into 3 smaller strings for x, y and z.

The x, y and z coordinates represents the x and y coordinates of the contours of a lake, and the depth (z).
One of the calculations which I have to do, is to calculate the surface area of the lake, using the formula (x[i]*y[i+1])-(x[i+1]*y[i]), where z(depth) = 0.

I can get my code to run perfectly, up until the x[i+1] and y[i+1], where it keeps giving me a value of 0.

Can someone please tell me how to fix this?

Here is my code;

{
    string[] ss = File.ReadAllLines(@"C:File.csv");

    for (int i = 1; i < ss.Length; i++)
    {
        string[] valuesAsString = ss[i].Split(new char[] { ' ', ',' }, StringSplitOptions.RemoveEmptyEntries);

        double[] X = new double[valuesAsString.Length];
        double[] Y = new double[valuesAsString.Length];
        double[] Z = new double[valuesAsString.Length];

        for (int n = 0; n < 1; n++)
        {
            X[n] = double.Parse(valuesAsString[0]);
            Y[n] = double.Parse(valuesAsString[1]);
        }

        do
        {
            double SurfaceArea = (X[n] * Y[n + 1]) - (X[n + 1] * Y[n]);

            Console.WriteLine(SurfaceArea);
        }

        while (Z[n] == 0);
   }
}

Answer 1

Ok, im not sure if i got it right, so you if you would take a look to what i did and tell me if its of any help.

After reviewng it a little i came up with the following:

A class for the values

    public class ValueXyz
    {
        public double X { get; set; }
        public double Y { get; set; }
        public int Z { get; set; }

    }

A class to manange the calculation:

    public class SurfaceCalculator
    {

    private ValueXyz[] _valuesXyz;
    private double _surface;
    private readonly string _textWithValues;

    public SurfaceCalculator(string textWithValues)
    {
        _textWithValues = textWithValues;
        SetValuesToCalculate();
    }

    public double Surface
    {
        get { return _surface; }
    }

    public void CalculateSurface()
    {

        for (var i = 0; i < _valuesXyz.Length; i++)
        {
            if (_valuesXyz[i].Z == 0)
                _surface = (_valuesXyz[i].X*_valuesXyz[i + 1].Y) - (_valuesXyz[i + 1].X*_valuesXyz[i].Y);
        }

    }


    private void SetValuesToCalculate()
    {
        var valuesXyz = _textWithValues.Split(' '); 


        _valuesXyz = valuesXyz.Select(item => new ValueXyz
                                                  {
                                                      X = Convert.ToDouble(item.Split(',')[0]),
                                                      Y = Convert.ToDouble(item.Split(',')[1]),
                                                      Z = Convert.ToInt32(item.Split(',')[2])
                                                  }).ToArray();

    }


}

So now your client code could do somethin like:

   [TestMethod]
    public void TestSurfaceCalculatorGetsAValue()
    {
        //var textWithValues = File.ReadAllText(@"C:File.csv");
        var textWithValues = "424.26,424.26,0 589.43,231.46,0 720.81,14.22,1";
        var calculator = new SurfaceCalculator(textWithValues);
        calculator.CalculateSurface();

        Assert.IsNotNull(calculator.Surface);
    }

I’m not very sure i got the idea correct of how to implement the formula, but i just wanted to expose an alternative you can use, you can never have to many ways of doing one thing :).

Cheers.

By the way part of the intent i had, was not tying up your funcionality to the csv in case your source for the text in the future would change.