System.Windows.Forms.DataVisualization.Charting.Utilities.HistogramChartHelper.CreateHistogram C# (CSharp) Method

        public void CreateHistogram(
            Chart chartControl,
            string dataSeriesName,
            string histogramSeriesName)
        {
            // Validate input
            if(chartControl == null)
            {
                throw(new ArgumentNullException("chartControl"));
            }
            if(chartControl.Series.IndexOf(dataSeriesName) < 0)
            {
                throw(new ArgumentException("Series with name'" + dataSeriesName + "' was not found.", "dataSeriesName"));
            }

            // Make data series invisible
            chartControl.Series[dataSeriesName].Enabled = false;

            // Check if histogram series exsists
            Series	histogramSeries = null;
            if(chartControl.Series.IndexOf(histogramSeriesName) < 0)
            {
                // Add new series
                histogramSeries = chartControl.Series.Add(histogramSeriesName);

                // Set new series chart type and other attributes
                histogramSeries.ChartType = SeriesChartType.Column;
                histogramSeries.BorderColor = Color.Black;
                histogramSeries.BorderWidth = 1;
                histogramSeries.BorderDashStyle = ChartDashStyle.Solid;
            }
            else
            {
                histogramSeries = chartControl.Series[histogramSeriesName];
                histogramSeries.Points.Clear();
            }

            // Get data series minimum and maximum values
            double	minValue = double.MaxValue;
            double	maxValue = double.MinValue;
            int		pointCount = 0;
            foreach(DataPoint dataPoint in chartControl.Series[dataSeriesName].Points)
            {
                // Process only non-empty data points
                if(!dataPoint.IsEmpty)
                {
                    if(dataPoint.YValues[0] > maxValue)
                    {
                        maxValue = dataPoint.YValues[0];
                    }
                    if(dataPoint.YValues[0] < minValue)
                    {
                        minValue = dataPoint.YValues[0];
                    }
                    ++pointCount;
                }
            }

            // Calculate interval width if it's not set
            if(double.IsNaN(this.SegmentIntervalWidth))
            {
                this.SegmentIntervalWidth = (maxValue - minValue) / SegmentIntervalNumber;
                this.SegmentIntervalWidth = RoundInterval(this.SegmentIntervalWidth);
            }

            // Round minimum and maximum values
            minValue = Math.Floor( minValue / this.SegmentIntervalWidth ) * this.SegmentIntervalWidth;
            maxValue = Math.Ceiling( maxValue / this.SegmentIntervalWidth ) * this.SegmentIntervalWidth;

            // Create histogram series points
            double currentPosition = minValue;
            for(currentPosition = minValue; currentPosition <= maxValue; currentPosition+=this.SegmentIntervalWidth)
            {
                // Count all points from data series that are in current interval
                int count = 0;
                foreach(DataPoint dataPoint in chartControl.Series[dataSeriesName].Points)
                {
                    if(!dataPoint.IsEmpty)
                    {
                        double	endPosition = currentPosition + this.SegmentIntervalWidth;
                        if(dataPoint.YValues[0] >= currentPosition &&
                            dataPoint.YValues[0] < endPosition)
                        {
                            ++count;
                        }

                        // Last segment includes point values on both segment boundaries
                        else if(endPosition >= maxValue)
                        {
                            if(dataPoint.YValues[0] >= currentPosition &&
                                dataPoint.YValues[0] <= endPosition)
                            {
                                ++count;
                            }
                        }
                    }
                }

                // Add data point into the histogram series
                histogramSeries.Points.AddXY(currentPosition + this.SegmentIntervalWidth / 2.0, count);
            }

            // Adjust series attributes
            histogramSeries["PointWidth"] = "1";

            // Adjust chart area
            ChartArea chartArea = chartControl.ChartAreas[histogramSeries.ChartArea];
            chartArea.AxisY.Title = "Frequency";
            chartArea.AxisX.Minimum = minValue;
            chartArea.AxisX.Maximum = maxValue;

            // Set axis interval based on the histogram class interval
            // and do not allow more than 10 labels on the axis.
            double axisInterval = this.SegmentIntervalWidth;
            while( (maxValue - minValue) / axisInterval > 10.0)
            {
                axisInterval *= 2.0;
            }
            chartArea.AxisX.Interval = axisInterval;

            // Set chart area secondary Y axis
            chartArea.AxisY2.Enabled = AxisEnabled.Auto;
            if(this.ShowPercentOnSecondaryYAxis)
            {
                chartArea.RecalculateAxesScale();

                chartArea.AxisY2.Enabled = AxisEnabled.True;
                chartArea.AxisY2.LabelStyle.Format = "P0";
                chartArea.AxisY2.MajorGrid.Enabled = false;
                chartArea.AxisY2.Title = "Percent of Total";

                chartArea.AxisY2.Minimum = 0;
                chartArea.AxisY2.Maximum =  chartArea.AxisY.Maximum / ( pointCount / 100.0 );
                double minStep = (chartArea.AxisY2.Maximum > 20.0) ? 5.0 : 1.0;
                chartArea.AxisY2.Interval = Math.Ceiling( (chartArea.AxisY2.Maximum / 5.0 / minStep) ) * minStep;

            }
        }

        private void UpdateChartSettings()
        {
            if(!this.loadingData)
            {
                // Create a histogram series
                HistogramChartHelper histogramHelper = new HistogramChartHelper();
                histogramHelper.SegmentIntervalNumber = int.Parse(comboBoxIntervalNumber.Text);
                histogramHelper.ShowPercentOnSecondaryYAxis = checkBoxShowPercents.Checked;
                // NOTE: Interval width may be specified instead of interval number
                //histogramHelper.SegmentIntervalWidth = 15;
                histogramHelper.CreateHistogram(chart1, "RawData", "Histogram");

                // Set same X axis scale and interval in the single axis data distribution
                // chart area as in the histogram chart area.
                chart1.ChartAreas["Default"].AxisX.Minimum = chart1.ChartAreas["HistogramArea"].AxisX.Minimum;
                chart1.ChartAreas["Default"].AxisX.Maximum = chart1.ChartAreas["HistogramArea"].AxisX.Maximum;
                chart1.ChartAreas["Default"].AxisX.Interval = chart1.ChartAreas["HistogramArea"].AxisX.Interval;
            }
        }