Add the ability to interact with curves on an existing plot

[Nick Draper]

Lots of this would be useful, but I can see it is a lot, we may have to cherry pick or split into separate tickets.

From QTIplot Handbook:

Working with 2D curves

You can then add or remove curves to or from this layer:

l.insertCurve(table, Ycolumn, type=Layer.Scatter, int startRow = 0, int endRow = -1)# returns a reference to the inserted curve
l.insertCurve(table, Xcolumn, Ycolumn, type=Layer.Scatter, int startRow = 0, int endRow = -1)# returns a reference to the inserted curve
l.addCurve(table, column, type=Layer.Line, lineWidth = 1, symbolSize = 3, startRow = 0, endRow = -1)# returns True on success
l.addCurves(table, (2,4), type=Layer.Line, lineWidth = 1, symbolSize = 3, startRow = 0, endRow = -1)# returns True on success
l.removeCurve(curveName)
l.removeCurve(curveIndex)
l.removeCurve(curveReference)
l.deleteFitCurves()
It is possible to change the order of the curves inserted in a layer using the following function:

l.changeCurveIndex(int oldIndex, int newIndex)
Sometimes, when performing data analysis, one might need the curve title. It is possible to obtain it using the method below:

title = l.curveTitle(curveIndex)
It is possible to get a reference to a curve on the layer l using it's index or it's title, like shown below:

c = l.curve(curveIndex)
c = l.curve(curveTitle)
dc = l.dataCurve(curveIndex)
Please, keep in mind the fact that the above methods might return an
 invalid reference if the curve with the specified index/title is 
not a PlotCurve or a DataCurve object, respectively. For example, an
 analytical function curve is a PlotCurve but not a DataCurve and 
spectrograms are a completely different type of plot items which are
 neither PlotCurves nor DataCurves.

Use the following function to change the axis attachment of a curve:


l.setCurveAxes(number, x-axis, y-axis)
where number is the curve's number, x-axis is either 0 or 1 (bottom or top) and y-axis is either 0 or 1 (left or right).

In case you need the number of curves on a layer, you can get it with

l.numCurves()
Once you have added a curve to a 2D plot, you can fully customize it's appearance:

l = newGraph().activeLayer()
l.setAntialiasing()
c = l.insertCurve(table("Table1"), "Table1_2", Layer.LineSymbols)
c.setPen(QtGui.QPen(Qt.red, 3))
c.setBrush(QtGui.QBrush(Qt.darkYellow))
c.setSymbol(PlotSymbol(PlotSymbol.Hexagon, QtGui.QBrush(Qt.yellow), QtGui.QPen(Qt.blue, 1.5), QtCore.QSize(15, 15)))
It is possible to change the number of symbols to be displayed for a curve using the function below. This option can be very usefull for very large data sets:

c.setSkipSymbolsCount(3)
print c.skipSymbolsCount()
An alternative way of customizing a curve is by using the functions below:

l.setCurveLineColor(int curve, int color) # uses the index of the colors in the default QtiPlot color list: 0 = black, 1 = red, 2 = green, etc...
l.setCurveLineStyle(int curve, Qt::PenStyle style)
l.setCurveLineWidth(int curve, double width)
You can also define a global color policy for the plot layer using the following convenience functions:

l.setGrayScale()
l.setIndexedColors() # uses the colors in the default QtiPlot color list: 0 = black, 1 = red, 2 = green, etc...
You can display labels showing the y values for each data point in a DataCurve:

c.setLabelsColumnName("Table1_2")
c.setLabelsOffset(50, 50)
c.setLabelsColor(Qt.red)
c.setLabelsFont(QtGui.QFont("Arial", 14))
c.setLabelsRotation(45)
c.loadData() # creates the labels and updates the display
and, of course, you can disable them using:

c.clearLabels()
l.replot() # redraw the plot layer object
If you need to change the range of data points displayed in a DataCurve you can use the following methods:

c.setRowRange(int startRow, int endRow)
c.setFullRange()
Also, you can hide/show a plot curve via:

c.setVisible(bool on)
In case you need to get information about the data stored in the curve, you have at your disposal the functions below:

points = c.dataSize()
for i in range (0, points):
	print i, "x = ", c.x(i), "y = ", c.y(i)

print c.minXValue()
print c.maxXValue()
print c.minYValue()
print c.maxYValue()
Curve symbols

Here's how you can customize the plot symbol used for a 2D plot curve c:

s = c.symbol()
s.setSize(QtCore.QSize(7, 7))# or s.setSize(7)
s.setBrush(QtGui.QBrush(Qt.darkYellow))
s.setPen(QtGui.QPen(Qt.blue, 3))
s.setStyle(PlotSymbol.Diamond)
l.replot() # redraw the plot layer object
The symbol styles available in QtiPlot are:
0
PlotSymbol.NoSymbol

1
PlotSymbol.Ellipse

2
PlotSymbol.Rect

3
PlotSymbol.Diamond

4
PlotSymbol.Triangle

5
PlotSymbol.DTriangle

6
PlotSymbol.UTriangle

7
PlotSymbol.LTriangle

8
PlotSymbol.RTriangle

9
PlotSymbol.Cross

10
PlotSymbol.XCross

11
PlotSymbol.HLine

12
PlotSymbol.VLine

13
PlotSymbol.Star1

14
PlotSymbol.Star2

15
PlotSymbol.Hexagon

It is also possible to define a custom image as the plot symbol for a curve:

g = newGraph().activeLayer()
c = g.addFunction("cos(x)", 0, 10, 20)
c.setSymbol(ImageSymbol("qtiplot/manual/html/icons/help.png"))
Here's a short script showing how to draw a custom plot symbol and assign it to a curve:

pix = QtGui.QPixmap(QtCore.QSize(11, 11))
pix.fill(Qt.transparent)
p = QtGui.QPainter(pix)
r = QtCore.QRect(0, 0, 10, 10)
p.drawEllipse(r)
p.setPen(QtGui.QPen(Qt.red))
p.drawLine(5, 0, 5, 10)
p.drawLine(0, 5, 10, 5)
p.end()

g = newGraph().activeLayer()
c = g.addFunction("sin(x)", 0, 10, 20)
c.setSymbol(ImageSymbol(pix))

[Nick Draper]

Bulk move of tickets at the end of iteration 28

[Nick Draper]

"New" tickets moved at the code freeze of iteration 29

[Nick Draper]

Bulk move of tickets to iteration 31 at the iteration 30 code freeze

[Russell Taylor]

Add ability to set a curve's symbol, pen & brush via python.

QwtSymbol is exposed as PlotSymbol and allows all aspects of the symbol to be customised. The setCurvePen method acts on the characteristics of the line and offers more advanced options than the setCurveLineColor/Style/Width methods. setCurveBrush acts on the area beneath a curve (e.g. fill colour, style...) Re #2656.

Changeset: f54a051d588704821b07568a685f0f5ce9d15af3

[Russell Taylor]

Add a Graph::insertCurve overload for adding Mantid curves. Re #2656.

Takes a workspace name and index and adds a 1D curve. Exposed this method to python, along with the overload that takes just the Y column name of a table.

Changeset: fa814ca588355e13c24300fcdca984b7123095a4

[Russell Taylor]

Later, I'll intercept the insertCurve method so that a reference to workspace can be given instead of (or as well as) the name.

[Russell Taylor]

Add curveTitle & setCurveAxes to python layer objects. Re #2656.

Changeset: 31754e5cc55e8e76c187844e6a2b8fc82164176d

[Russell Taylor]

Add the ability to use a custom symbol on a plot. Re #2656.

Seems slightly frivolous, but it was easy so why not. Involved bringing in the ImageSymbol class from today's QtiPlot and exposing to python. A custom symbol can be loaded from an image file or drawn using the QPixmap class.

Changeset: 5a9bd8c84616908d3c629b984a89ed8d5b6bc2ce

[Russell Taylor]

Indentation fixes only. Re #2656.

Changeset: 2ffcd8ea77f936494b8476297f999697b2c11fc9

[Russell Taylor]

Indentation/formatting only. Re #2656.

Changeset: b14f31ca337df4e06681a70951cfb57ba9b4f662

[Russell Taylor]

Add possibility to draw only every n'th symbol on a 1D plot. Re #2656.

Back-ported in from today's QtiPlot.

Changeset: 19e2007c71dc94d75f0d677e60a78475a532e4d4

[Russell Taylor]

Retain skipped symbols in Mantid curves on reloading a saved project.

Re #2656.

Changeset: b90293339ffe2300c6d19d277a96b5b747854281

[Russell Taylor]

Indentation/formatting changes only. Re #2656.

Changeset: d9e9c1fa3f62e9520446e8297ca9c392d5824b5f

[Russell Taylor]

Draw error bars only when symbol is drawn (non-Mantid curves only).

Re #2656. Will address greater control of when error bars are drawn, including for Mantid curves under #2657.

Changeset: aa78ad5c34ca194678e2301c2c5ca56379108148

[Russell Taylor]

Add setGrayScale & setIndexedColors methods to Graph. Re #2656.

Allows switching all curves on a plot between grayscale and colour. Exposed to python.

Changeset: cebbed0e01455b24c899b2499ba72c91b5f63425

[Russell Taylor]

Expose arguments on insertCurve that allow plotting only a range...

...of rows from a table. Re #2656.

Changeset: 1130ba4c27e17537656b6fe0e288dbfea3480d06

[Russell Taylor]

Almost everything in the description has now been implemented, with a few exceptions.

The most notable of these is that I decided not to expose the curve classes themselves. However, most of the actions can be accomplished through calling methods on Graph instead - e.g. l.setCurveSkipSymbolsCount(curveNum,3) instead of c.setSkipSymbolsCount(e).

The following items are missing:

• Changing a curve's index (l.changeCurveIndex)
• Showing and customising labels on individual points
• Changing the range of points (e.g. rows of a table) that are plotted
• Hiding a curve (except by removing it)
• Retrieving the data values/min/max of a curve
• Retaining a custom symbol (from file or 'hand drawn') after saving & reloading a project

I still need to update our wiki documentation before closing this ticket.

[Russell Taylor]

Have Layer.insertCurve accept a WorkspaceProxy. Re #2656.

Also a bit more pertaining to #1037.

Changeset: 6c05dfba404e7a1f0b6965573c85ad02e6a6a78d

[Russell Taylor]

Forgot that I still need to do the documentation.....

[Nick Draper]

Moved to iteration 33 at iteration 32 code freeze

[Russell Taylor]

Documentation is at: http://www.mantidproject.org/MantidPlot:_Working_with_1D_curves

[Russell Taylor]

A small fix to pass through call. Re #2656.

Changeset: 4be9f43c5ead234ccb30a0805cc3876e87756663

[Nick Draper]

Tested on Windows 7 64 bit

particularly liked this one

g = newGraph().activeLayer()
g.addFunction("cos(x)", 0, 10, 20)
g.setCurveSymbol(0, ImageSymbol("C:/Mantid/Documents/Images/Mantid Icon32.gif"))

[Stuart Campbell]

This ticket has been transferred to github issue ​3503