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Last modified: December 2007

URL: http://cxc.harvard.edu/chips4.0/Attributes.sl.html
AHELP for ChIPS 4.0 attributes Context: sl.chips

Synopsis

Attributes are used to configure object properties such as color, font, and line style.

Description

ChIPS allows users to control the appearance and behavior of objects - such as windows, curves, lines, contours, and axes - via configurable attribute settings. For instance, labels have a font, color, font size, font style, angle, and alignment attributes. The add_<object> and set_<object> help files have a list of the attributes for each object.

Attribute Objects

Attribute objects are structures for setting and retrieving attribute values of objects. A blank object is created from object constructors, such as ChipsLabel, then the values are set and applied to the object.

      l=ChipsLabel();
      l.color="darkred";
      set_label(l);
      

Values set to "NULL" have no effect on existing attribute values.

The get_<object> commands return a structure of attributes for the specifed object populated with the current values.

Attribute Lists

Attribute lists consist of any number of attribute/value pairs. The syntax for the list is: attribute1, value1, attribute2, value2, ... attributeN, valueN.

      add_curve(x,y,["line.color", "coral"]);
      set_curve(["symbol.color","red", "symbol.size",10]);
      

As shown, the list syntax may be used when adding a new object or when updating the settings of an existing object.

If the attribute list is specified during an add_<object> command, it may include attributes for other objects that will be created by the call, e.g. adding a curve will create a plot and axes if they do not exist.

Attribute Strings

An attribute string is a space-delimited list of attribute/value pairs which may be used to set values of object attributes. The syntax for the string is: attribute1=value1 attribute2=value2 ... attributeN=valueN.

  
      add_curve(x,y,"axis.color=lime curve.line.color=cornflower");
      

The attribute string may only be used in an add_<object> command. It cannot be used to change the properties of an existing object.

Individual Attributes

There are also lower-level commands in ChIPS to set individual object attributes.

      set_curve_linecolor("red");
      set_frame_transparency("frm1",True);
      

These commands are equivalent to using set_<object> with an attribute/value pair.

Example 1

chips> add_label(100,100,"Fig. B",{"color", "blue", "size", "8" });

Create a blue label, specifying the attribute values in a list.

Example 2

chips> add_region({1,1,2,2.32,2},{1.5,2,2,1,1},"fill.visible=true
fill.color=blue");
chips> add_region({3,2.67,3},{1,2,2.2},"fill.visible=true
fill.color=lime");

Add two regions, using an attribute string.

Example 3

chips> settings = ChipsFrame;
chips> settings.border.color = "blue";
chips> settings.border.visible = 1;
chips> set_frame("frame1",settings);

Populate the "settings" structure with attribute values, then use it to set frame1 to have a blue border

Example 4

chips> add_frame(.1, .1, .5, .5);
chips> set_frame({"bgcolor","tan"});
chips> add_frame(.5, .5, .9, .9);
chips> set_frame({"bgcolor","white"});

Two frames are created, and the background color of each is set with an individual attribute command.

Bugs

See the bugs pages on the ChIPS website for an up-to-date listing of known bugs.

Last modified: December 2007



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