This is my first project in c# and I'm trying to create plots from data.
I'm struggling with drawing minor and major grid lines and labels on a logarithmic scale.
I've set the scale to logarithmic, set the base to 10 and both major and minor intervals to 1, and it works great, however, the interval starts with the minimum value on scale, so for example if data starts at 30M (I'm dealing with frequencies) the next major tick is at 300M and 3G, which is not as it should be.
Is there a way to set major grid to 1, 10, 100 etc, independent of what data is displayed? i've tried changing intervals, base and offset but have not achieved much.
area.AxisX.IsLogarithmic = true;
area.AxisX.LogarithmBase = 10;
area.AxisX.Interval = 1;
//area.AxisX.IntervalOffset = 10000;
area.AxisX.IntervalAutoMode = IntervalAutoMode.FixedCount;
area.AxisX.MajorGrid.Enabled = true;
area.AxisX.MajorTickMark.Enabled = true;
area.AxisX.MinorGrid.Enabled = true;
area.AxisX.MinorGrid.Interval = 1;
area.AxisX.MinorTickMark.Enabled = true;
area.AxisX.MinorTickMark.Interval = 1;
area.AxisX.Minimum = minMaxXY[0]; // in this example 30 M
area.AxisX.Maximum = minMaxXY[1]; // in this example 1 G
here's the link to the current grid
https://ibb.co/3WkxLfc
Thank you for your time and answers!
Thanks to TaW replay I managed to get my program working.
Here is my solution using customLabels location to draw the grid lines.
private void Chart1_PostPaint(object sender, ChartPaintEventArgs e)
{
if (e.Chart.ChartAreas.Count > 0) // I don't yet truly understand when this event occurs,
// so I got plenty of null references.
{
Graphics g = e.ChartGraphics.Graphics;
g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.AntiAliasGridFit;
Color minorGridColor = Color.Gainsboro;
ChartArea area = e.Chart.ChartAreas[0];
double aymin = area.AxisY.Minimum;
double aymax = area.AxisY.Maximum;
int y0 = (int)area.AxisY.ValueToPixelPosition(aymin);
int y1 = (int)area.AxisY.ValueToPixelPosition(aymax);
foreach (var label in chart1.ChartAreas[0].AxisX.CustomLabels)
{
double xposition = area.AxisX.ValueToPixelPosition(Math.Pow(10, label.FromPosition + 0.1));
if (xposition > area.AxisX.ValueToPixelPosition(minMaxXY[0]) && xposition < area.AxisX.ValueToPixelPosition(minMaxXY[1]))
//this prevents drawing of lines outside of the chart area
{
int x = (int)xposition;
using (Pen dashed_pen = new Pen(Color.FromArgb(10, 0, 0, 0), 1))
{
dashed_pen.DashStyle = System.Drawing.Drawing2D.DashStyle.Dash;
g.DrawLine(dashed_pen, x, y0, x, y1);
}
}
}
}
}
I also found the CustomLabel.GridTicks Property, but for some reason it did not work.
Related
I'm currently working on a project, in which I need to create a Polar Plot with dynamically generated data. I've managed to create a somewhat decent polar plot, but have not been able to create what is needed.
This is my Polar Plot
this is the code I used to set the offset in the middle:
public Form1()
{
InitializeComponent();
chart1.ChartAreas[0].AxisX.MajorTickMark.Enabled = false;
chart1.ChartAreas[0].AxisX.MajorGrid.Enabled = false;
chart1.ChartAreas[0].AxisY.Minimum = -20;
chart1.ChartAreas[0].AxisY.MajorGrid.IntervalOffset = 15;
chart1.ChartAreas[0].AxisY.MajorGrid.Interval = 5;
chart1.ChartAreas[0].AxisY.MajorGrid.LineDashStyle = ChartDashStyle.Solid;
chart1.ChartAreas[0].AxisX.MajorGrid.LineDashStyle = ChartDashStyle.Solid;
}
I found some help here: How to displace the origin of the Y axis on a polar Mschart?
I got a example on how I'm trying to get the polar:
The finished example
I don't think you can make an axis start from anywhere but its minimum.
(The linked post only makes the labels start from a different value.)
So we'll have to help with a little bit of owner-drawing.
A few short references:
var ca = chart1.ChartAreas[0];
var ax = ca.AxisX;
var ay = ca.AxisY;
Now let's hide the y-axis:
ay.LineWidth = 0;
To draw the portion of the axis from the interval offset to the maximum we simply code the PostPaint event:
private void chart1_PostPaint(object sender, ChartPaintEventArgs e)
{
// add references..
..
// then use values to calulate pixel coordinates..
int py1 = (int)ay.ValueToPixelPosition(ay.Minimum + ay.IntervalOffset);
int py2 = (int)ay.ValueToPixelPosition(ay.Maximum);
int px = (int)ax.ValueToPixelPosition(ax.Maximum - ax.Minimum);
// blue to make it stand out
e.ChartGraphics.Graphics.DrawLine(Pens.Blue, px, py1, px, py2);
}
Result:
Of course finding the right values for Interval, IntervalOffset, Minimum and Maximum is all up to you..
Update: If you want to have a full set of shortened x-axis gridlines you could do a lot of math or use a graphics transform. As usual the latter is so much easier..:
Graphics g = e.ChartGraphics.Graphics;
int pyc = (int)ay.ValueToPixelPosition(ay.Minimum); // y-center
for (int i = 0; i < 360 / ax.Interval; i++)
{
g.TranslateTransform(px, pyc);
g.RotateTransform((float)(i * ax.Interval));
g.TranslateTransform(-px, -pyc);
g.DrawLine(Pens.colorOfYourChoice, px, py1, px, py2);
g.ResetTransform();
}
After setting ax.Interval = 30; we get this result:
I have to have static space (lets say 20 px) between axes.
If I have more axes on the left, it is possible to set their StartPosition and EndPosition in pixels or in percents.
For pixels setting - is there some way, how I can get the height of the space, where are the axes (red line in the picture)?
For percents setting - is there some way, how I can automatically convert 20 px to percents? I could calculate that by myself if I know the height, but I don't know how to get it - see 1.
I am able to get the height of the whole panel, where the chart is, but I don't know where to get the actual height of the space for left axes.
tChart1.Chart.ChartRect gives you the Rectangle of the "drawing zone". In your case, where you have to get that size before the axes calculations, you can use GetAxesChartRect event and use e.AxesChartRect as follows:
private void testChartRect()
{
for (int i = 0; i < 4; i++)
{
Line line = new Line(tChart1.Chart);
tChart1.Series.Add(line);
line.Chart = tChart1.Chart;
line.FillSampleValues();
Axis axis = new Axis();
tChart1.Axes.Custom.Add(axis);
line.CustomVertAxis = axis;
axis.AxisPen.Color = line.Color;
axis.Labels.Font.Color = line.Color;
}
tChart1.Aspect.View3D = false;
tChart1.Panel.MarginLeft = 10;
//tChart1.AfterDraw += TChart1_AfterDraw1;
tChart1.GetAxesChartRect += TChart1_GetAxesChartRect;
}
private void TChart1_GetAxesChartRect(object sender, GetAxesChartRectEventArgs e)
{
Rectangle chartRect = e.AxesChartRect;
int axisLength = (chartRect.Bottom - chartRect.Top) / tChart1.Axes.Custom.Count;
int margin = 20;
for (int i = 0; i < tChart1.Axes.Custom.Count; i++)
{
Axis axis = tChart1.Axes.Custom[i];
axis.StartEndPositionUnits = PositionUnits.Pixels;
axis.StartPosition = i * axisLength;
axis.EndPosition = (i + 1) * axisLength - (i != (tChart1.Axes.Custom.Count - 1) ? margin : 0);
}
}
private void TChart1_AfterDraw1(object sender, Graphics3D g)
{
tChart1.Graphics3D.Brush.Color = Color.Red;
tChart1.Graphics3D.Brush.Transparency = 80;
tChart1.Graphics3D.Rectangle(tChart1.Chart.ChartRect);
}
This question already has an answer here:
chart x-axis numbering
(1 answer)
Closed 5 years ago.
I am using .Net Charts. In that, I have displayed a line chart with an Interval of 28 Days.
Here is my code:
Chart1.ChartAreas["ChartArea1"].AxisX.IntervalOffset = 1;
Chart1.ChartAreas["ChartArea1"].AxisX.Minimum = min;
Chart1.ChartAreas["ChartArea1"].AxisX.Maximum = max;
Chart1.ChartAreas["ChartArea1"].AxisX.Interval = 28;
But, one of my situation comes like,
28 Days Interval, 35 Days Interval, 28 Days Interval etc. Is that possible to have different Intervals.
No, Interval is an Axis property and there can only be one.
You can work around this restriction by drawing gridlines and labels on your own.
Let's assume you have a list of stop points, i.e. the indices of the DataPoints where you want a GridLine to appear:
List<int> stops = new List<int>();
After adding a few test numbers stops.AddRange(new[] { 12, 23, 42, 52, 82 }); we can code the PostPaint event of the Chart to draw lines:
private void chart_PostPaint(object sender, ChartPaintEventArgs e)
{
Graphics g = e.ChartGraphics.Graphics;
g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.AntiAliasGridFit;
ChartArea ca = chart.ChartAreas[0];
Font font = ca.AxisX.LabelStyle.Font;
Color col = ca.AxisX.MajorGrid.LineColor;
int padding = 10; // pad the labels from the axis
double aymin = ca.AxisY.Minimum;
double aymax = ca.AxisY.Maximum;
int y0 = (int)ca.AxisY.ValueToPixelPosition(aymin);
int y1 = (int)ca.AxisY.ValueToPixelPosition(aymax);
foreach (int sx in stops)
{
int x = (int)ca.AxisX.ValueToPixelPosition(chart.Series[0].Points[sx].XValue);
using (Pen pen = new Pen(col))
g.DrawLine(pen, x, y0, x, y1);
string s = chart.Series[0].Points[sx].XValue + "";
if (ca.AxisX.LabelStyle.Format != "") s = string.Format(ax.LabelStyle.Format, s);
SizeF sz = g.MeasureString(s, font, 999);
g.DrawString(s, font, Brushes.Black, (int)(x - sz.Width / 2) , y0 + padding);
}
}
After turning off the original MajorGrid etc..
ChartArea ca = chart.ChartAreas[0];
ca.AxisX.MajorGrid.Enabled = false;
ca.AxisX.MajorTickMark.Enabled = false;
ca.AxisX.LabelStyle.Enabled = false;
..this is the result:
Notes:
Most of the code are just simple preparations and references. The actual drawing are 2 methods and three or four more lines to get the coordinates..
I have stored the DataPoint indices in my List. If you want the custom GridLines to be independent of DataPoints you can instead store the Values and change the List to a List<double> andthe two references from chart.Series[0].Points[sx].XValue
to accessing the stop values sx directly.
Change the padding value to suit you..
We can access the axes' minima and maxima values freely, even if they are actually set to Auto. This is because we are in a Paintevent. Otherwise we would have to call RecalculateAxesScale() on the ChartArea..
Feel free to make the Black label brush dynamic as well..
So I'm writing a program that generates a chart and saves it to PNG. From what I've read, if I were drawing to a window, it doesn't behave this way, but I'm not doing that.
The problem is that when I pass the brush I use to draw the label to another method to do the drawing, sometimes the text comes out looking bold. Also, the Y coordinate seems to have something to do with it, since it happens on every other row of the chart I'm drawing. And it's not a nice bold, either, it's like a gritty, messy looking bold. Some people have suggested changing the text rendering hint to antialiased, and it solves the "bolding" problem, but it doesn't look as nice as ClearType.
Note that none of this happens if I do everything in one method without passing the brush around, which is the most puzzling part of this. Any ideas?
Here's some of the code:
// Draw the timeline.
int y = 0;
bool shadeRow = true;
foreach (TimelineRow row in timeline.chart)
{
int rowHeight = row.height + TimelineRow.ROW_GAP;
if (shadeRow)
{
g.FillRectangle(shadeBrush, 0, y, chartWidth, rowHeight);
}
// Draw name labels, guidelines, and timeline row.
g.DrawString(row.name, labelFont, labelBrush, PADDING, (int)Math.Ceiling(y + (float)PADDING / 2));
for (int i = 0; i < row.years.Length; i++)
{
int blockX = labelsWidth + i * TimelineRow.DEFAULT_HEIGHT;
g.DrawLine(i % 5 == 0 ? yearGridDark : yearGridLight, blockX, y, blockX, y + rowHeight);
}
DrawRow(row, g, labelsWidth, y + 8);
y += rowHeight;
shadeRow = !shadeRow;
}
// Draw the year labels
int x = labelsWidth;
for (int year = timeline.startYear; year <= timeline.endYear; year += 5)
{
string yearString = Convert.ToString(year);
int width = (int)g.MeasureString(yearString, labelFont).Width;
g.DrawString(yearString, labelFont, labelBrush, x - width / 2, y);
x += 5 * TimelineRow.DEFAULT_HEIGHT;
}
I've had similar issues with drawing strings. In my cases, clearing the image FIRST with the background color has fixed the problem.
Wow, that actually did it.
Use Graphics.Clear() to set the initial color:
Bitamp bmp = new Bitmap(...);
Graphics g = Graphics.FromImage(bmp);
g.Clear(Color.White);
// ... now draw with "g" ...
I've spent hours trying to solve this silly problem. I create an histogram with asp chart control. All I want to do is have the xaxis label on the left of the column instead of centered on it. Xaxis lable doesn't seem to have a position property like series do, so I can't figure it out and it's frustrating.
Here's a sample code of the type of graphic I'm talking about to show you what I get approximately:
private void Graphique()
{
// Creating the series
Series series2 = new Series("Series2");
// Setting the Chart Types
series2.ChartType = SeriesChartType.Column;
// Adding some points
series2.Points.AddXY(1492, 12);
series2.Points.AddXY(2984, 0);
series2.Points.AddXY(4476, 1);
series2.Points.AddXY(5968, 2);
series2.Points.AddXY(7460, 2);
series2.Points.AddXY(8952, 12);
series2.Points.AddXY(10444, 4);
series2.Points.AddXY(11936, 3);
series2.Points.AddXY(13428, 3);
series2.Points.AddXY(14920, 5);
series2.Points.AddXY(16412, 1);
Chart3.Series.Add(series2);
Chart3.Width = 600;
Chart3.Height = 600;
// Series visual
series2.YValueMembers = "Frequency";
series2.XValueMember = "RoundedValue";
series2.BorderWidth = 1;
series2.ShadowOffset = 0;
series2.IsXValueIndexed = true;
// Setting the X Axis
Chart3.ChartAreas["ChartArea1"].AxisX.IsMarginVisible = true;
Chart3.ChartAreas["ChartArea1"].AxisX.Interval = 1;
Chart3.ChartAreas["ChartArea1"].AxisX.Maximum = Double.NaN;
Chart3.ChartAreas["ChartArea1"].AxisX.Title = "kbps";
// Setting the Y Axis
Chart3.ChartAreas["ChartArea1"].AxisY.Interval = 2;
Chart3.ChartAreas["ChartArea1"].AxisY.Maximum = Double.NaN;
Chart3.ChartAreas["ChartArea1"].AxisY.Title = "Frequency";
}
Now my real chart looks like this, Actual result
I would like something similar to this website :
Desired layout chart
You see, the x label is on the left, which makes way more sense considering that each column of an histogram represents the frequency of a range of values.....
Any help would be appreciated...
Did you try to add CustomLabels to replace the default ones? For example:
for (int i = 0; i <= 10; i++) {
area.AxisX.CustomLabels.Add(i + 0.5, i + 1.5, i, 0, LabelMarkStyle.None);
}
The first two are for positioning and the third would be the text value of the label.