System Overflow Exception in System.Windows.Forms.DataVisualization.dll

Question

I've got problem that makes me crazy - I think that's so easy that I can't even think about what is causing my problems.

I'm sending data (fft of generated acustic wave - frequencies and magnitude) generated by my uC to PC by serialport.

Everything seems to work fine till I try to chart my data with MS Chart Controls - without charting there are no errors when recieving data. I'm always able to chart data once or twice, after that I'm getting error like this:

An unhandled exception of type 'System.OverflowException' occurred in System.Windows.Forms.DataVisualization.dll

Additional information: Value was either too large or too small for a Decimal.

I checked if vaules of data are over limits of "float32" aka Single - I even applied statement where I make values lower when they are too high - it's useless. The part of my with recievedata event and charting is like this:

private byte[] bArray = new byte[20 * numberOfSamples + 4]; // frequencies (512 samples) and magnitudes (512 values) - each is a single precision float so 4 bytes + 4 - "!!!!" at the beginning
private float[] fArray = new float[2 * numberOfSamples + 1]; // float data array


        private void SerialP_DataReceived(object sender, SerialDataReceivedEventArgs e)
    {
        SerialPort sp = (SerialPort)sender;


        int previouse = counterOfRecBytes;

        counterOfRecBytes += sp.BytesToRead;
        //if (counterOfRecBytes >= 4104) 

        sp.Read(bArray, previouse, (counterOfRecBytes - previouse));

        if (counterOfRecBytes >= 8 * numberOfSamples + 4)
        {
            for (uint i = 0; i < 2 * numberOfSamples + 1; i++)
            {
                fArray[i] = Math.Abs(ByteToFloat(bArray, i));
                if (fArray[i] < 0) fArray[i] = 0;
                if (fArray[i] > 3.4 * Math.Pow(10, 38) || fArray[i] < -3.4 * Math.Pow(10, 38)) fArray[i] = 0;
            }

            if (InvokeRequired)
            {
                Invoke(new MethodInvoker(ChartData));
            }
            else
            {
                ChartData();
            }

            // Set counterOfRecBytes to recieve new data
            counterOfRecBytes = 0;
        }



    }

    ///// <summary>
    ///// Changes my recieved bArray to single precision floats
    ///// </summary>
    private float ByteToFloat(byte[] input, UInt32 i)
    {
        byte[] array = new[] { input[4 * i], input[4 * i + 1], input[4 * i + 2], input[4 * i + 3] };
        return BitConverter.ToSingle(array, 0);
    }

    /// <summary>
    /// Setting chart data
    /// </summary>
    private void ChartData()
    {

        chart1.Series["Widmo"].Points.Clear();

        for(int i = 1; i < numberOfSamples + 1; i++)
        {
            chart1.Series["Widmo"].Points.AddXY(fArray[i], fArray[i + numberOfSamples]);
        }

    }

check that your floats are bigger than `decimal.MinValue` and smaller than `decimal.MaxValue`. Because the error is complaining about that — Pablo Recalde, Feb 13 '17 at 13:49
@grek40 I was checking if values of my floats arent out of range. I'm begginer when it comes to programming. — Jejh, Feb 13 '17 at 13:51
@grek40 Tried but that's not it. I think that "System.Windows.Forms.DataVisualization" is casting values that I put inty x & y to decimal type and then I get overflow. — Jejh, Feb 13 '17 at 14:23
Quite possible... how about checking for decimal range then? Approx `-7.9 x 10^28 to 7.9 x 10^28` (https://msdn.microsoft.com/en-us/library/364x0z75.aspx). Or better, start with decimal range in your data instead of casting later. — grek40, Feb 13 '17 at 14:28
@grek40 Well, the problem is that data I recieve are floatts(single precision) cut in 4 bytes each. My uC libs have fft function that returns float data — Jejh, Feb 13 '17 at 21:30

System Overflow Exception in System.Windows.Forms.DataVisualization.dll

0 Answers0