Changing its appearance

Some aspects of a graph's appearance such as the colour of a curve or the colour of the bars in a histogram can be changed when you call the CCATSL routine. Another set of simple customisations is governed by the AxisModeCT (see below). Other possible modifications include: changing the ranges (XRangeCL), the colours (GAxisColoursCL, GBrushStyleCL and GLineColourCL), the line style (GLineStyleCL), the line `mode' (GLineModeCL), the number of subdivisions of the axes (XIntervalsCL), the graph origin (XOriginCL) or the viewing direction for 3D plots (XViewPointCL).

AxisModeCT

All the CCATSL plotting routines, like CurveCL for example, take as their last argument a variable of type AxisModeCT. This must be one of PRESET, RESCALE, DRAWAXES and AUTOAXES. The most useful is AUTOAXES, which asks CCATSL to work out several things, such as sensible scales for the axes, and good places for the pip marks (small lines on the axes) and pip labels (small numbers appearing next to the pip marks). CCATSL then draws the axes, pip marks, pip labels, axes labels (which by default are blank) and finally the graph itself, all in the current graphics window.

If you would like CCATSL to work out scales for the axes as usual, but only to draw the curve, and none of the axes, pip marks, pip labels or axes labels, you use RESCALE.

If you are trying to draw a graph on the same set of axes as a previous graph (so you already have the axes, pip marks, pip labels and axes labels drawn and you don't want the scales recalculated), you use PRESET, which just draws the curve.

If you want to specify your own ranges for the $x$, $y$ or $z$-axes (perhaps you are only interested in a small part of the graph) you can use XRangeCL, YRangeCL and ZRangeCL to change the scales. You now don't want CCATSL to recalculate the ranges, but you do want the axes etc. drawn. In this case, you use DRAWAXES.

XRangeCL, YRangeCL and ZRangeCL

These routines allow you to change the range of values plotted on the $x$, $y$ and $z$ axes. They all have the same syntax so we will just describe XRangeCL below.

	void XRangeCL (	double l,
		double h);

l, h

Specifies the new $x$ range as $[l, h]$.

XOriginCL, YOriginCL and ZOriginCL

These routines allow you to change the origin of the subsequent graphs (i.e. the point where the axes cross). They all have similar declarations so we will just describe XOriginCL below.

	void XOriginCL (	double x);

x

The new $x$-coordinate of the orgin.

XIntervalsCL, YIntervalsCL and ZIntervalsCL

These routines allow you to change the number of intervals into which each axis is subdivided. They all have similar declarations so we will just describe XIntervalsCL below.

	void XIntervalsCL (	int n);

n

The new number of subdivisions for the axis.

ViewPointCL

ViewPointCL changes the point from which 3D perspective plots are viewed.

	void ViewPointCL (	double theta,
		double phi);

	theta		The new (Eulerian) angle $\theta$ of the viewing direction.
	phi		The new (Eulerian) angle $\phi$ of the viewing direction.

GAxisColoursCL

This routine allows you to change the colours used to draw the pip marks, the axes, and the axis labels

	void GAxisColoursCL (	ColourCT pipclr,
		ColourCT axisclr,
		ColourCT labelclr);

	pipclr		The colour for the pip marks.
	axisclr		The colour for the axes.
	labelclr		The colour for the axis labels.

GLineColourCL

This routine changes the main colour used in graph-drawing operations, including plot symbols and grid lines (see XYSymbolCL, GGridCL and GBoxCL).

	void GLineColourCL (	ColourCT clr);

clr

The new graphics colour.

GLineStyleCL

This routine changes the style and width of lines produced by graphics routines.

	void GLineStyleCL (	LineStyleCT style,
		int width);

	style		Possible values are SOLID_LINE, DASH_LINE, DOT_LINE, DASHDOT_LINE, DASHDOTDOT_LINE, and NULL_LINE.
	width		The thickness of the pen, in pixels.

GLineModeCL

This routine changes the way new lines appear when they cross existing lines.

	void GLineModeCL (	LineModeCT n);

n

The new line mode, one of NORMAL_MODE, INVERT_MODE, EOR_MODE, OR_MODE or AND_MODE.

GBrushStyleCL

This routine changes the colour and style of the brush used in fill operations such as XYPolygonFillCL.

	void GBrushCL (	ColourCT clr,
		BrushStyleCT k);

	clr		The new brush colour.
	k		See here for a list of available brush styles.