Hello,

I have a bar chart where the Y axis measures a distance between 0 and, say, 300 cm. I need a way to rescale the Y-Axis maximum value whenever a value comes in above the current maximum on the Y-Axis scale. I'm currently doing this by brute force, but I suspect there's an easier way of doing this using an existing Nevron chart feature, similar to what is described here:

http://support.nevron.com/KB/a219/create-a-custom-axis-view-that-updates-the-y-axis-range.aspx

Here's the relevant parts of my code. The AddBarData() method determines if the length (Y-Axis value) exceeds the maximum scale. If so, it calculates a new Y-Axis maximum value, then calls SetChart to redraw the chart with the new scale. The downside to this method, is I keep a running history of the bar values, and force a redraw. This probably isn't necessary, hence my question.

Thanks for any and all help on this.


public partial class NevronChart : UserControl, INevronChart
{
NChart chart;
NBarSeries barSeries;
NLabel title;
bool bDisplayOrthogonal;
bool bMetric;
double MaxLength;
double MaxTimeOfFlight;
double[] datapoint;

public void SetChart(bool bOrthogonal, bool bDefault, bool bIsMetric)
{
NLinearScaleConfigurator yScale = new NLinearScaleConfigurator();
bDisplayOrthogonal = bOrthogonal;

ClearData();

if (bDefault)
{
MaxLength = 300.0; // centimeters
}
barSeries.Name = "Length";
AddTitle("Length");

// Setup Y axis
yScale.MajorGridStyle.SetShowAtWall(ChartWallType.Back, true);
yScale.MajorGridStyle.SetShowAtWall(ChartWallType.Left, true);
yScale.MajorGridStyle.LineStyle.Pattern = LinePattern.Solid;

// Setup Y ticks
// Setting the text of the title.
if (bIsMetric)
yScale.Title.Text = "Length (cm)";
else
yScale.Title.Text = "Length (in)";

// Setting the angle between the axis and the title.
yScale.Title.Angle = new NScaleLabelAngle(-90);

// Setting the offset of the axis title.
yScale.Title.Offset = new NLength(0);

// Setting the title alignment.
// yScale.Title.RulerAlignment = Nevron.HorzAlign.Center;

// Setting the title ruler offset.
yScale.Title.RulerOffset = new NLength(2, NRelativeUnit.ParentPercentage);

// Setting the title content alignment.
yScale.Title.ContentAlignment = ContentAlignment.MiddleCenter;

yScale.MajorTickMode = MajorTickMode.CustomStep; // AutoMaxCount
if (bIsMetric)
{
yScale.CustomStep = 20;
yScale.AutoMinorTicks = true;
yScale.MinorTickCount = 1;
yScale.MinTickDistance = new NLength(10);
yScale.UseOrigin = true;
}
else
{
yScale.CustomStep = 10;
yScale.AutoMinorTicks = true;
yScale.MinorTickCount = 1;
yScale.MinTickDistance = new NLength(10);
yScale.UseOrigin = true;
}

yScale.LabelValueFormatter = new NNumericValueFormatter("#.##"); // ????
chart.Axis(StandardAxis.PrimaryY).ScaleConfigurator = yScale;
if (bIsMetric)
chart.Axis(StandardAxis.PrimaryY).View = new NRangeAxisView(new NRange1DD(0.0, MaxLength), true, true);
else
chart.Axis(StandardAxis.PrimaryY).View = new NRangeAxisView(new NRange1DD(0.0, MaxLength/2.54), true, true);
}

ApplyLayoutTemplate(0, chart, title, null);
}

public bool AddBarData(double[] safearray, int idx)
{

int i;


double maxheight = (bMetric) ? MaxHeight : MaxHeight / 2.54;
if (safearray[idx + 1] > maxheight)
{
int cnt = (int)safearray[idx] - 1;

if (bMetric)
MaxHeight = maxheight + 10;
else
MaxHeight = (maxheight * 2.54) + 10;
this.SetChart(true, false, bMetric);
ClearData();
for (i = 0; i < cnt; i++)
barSeries.AddDataPoint(new NDataPoint((double)i + 0.5, datapoint[i])); // 1..10
}

datapoint[(int)(safearray[idx] - 1.0)] = safearray[idx + 1];

barSeries.AddDataPoint(new NDataPoint(safearray[idx] - 0.5, safearray[idx + 1])); // 1..10

nChartControl1.Refresh();

return (false);
}
}