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Last modified: December 2013

URL: http://cxc.harvard.edu/chips/ahelp/get_label.html
AHELP for CIAO 4.6 ChIPS v1

get_label

Context: labels

Synopsis

Retrieves the attribute value(s) of the label.

Syntax

get_label()
get_label(id)
get_label(id, attribute)

Description

The function arguments.

Argument Description
id A ChipsId structure identifying the item, or a string containing the name of the object.
attribute The name of the attribute to retrieve, such as 'halign' or 'fontstyle'.

The get_label command returns a structure containing all the attribute values of the label. To retrieve the value of a specific attribute, provide the attribute name and the id or ChipsId of the object.

Some values are set to "None" in the returned structure. These entries generally correspond to attributes which may only be modified at creation time, such as the object id.

Please see the section "Label Preferences and Attributes" below the examples for a list of the label attributes.

Note that the label text is not included in the attributes. In order to get that value, use the get_label_text command.

To see if a label is hidden or visible, use the get_label_visible command.

Advanced Functions

The module of advanced ChIPS functions contains other commands for retrieving attribute values (refer to "ahelp chips" for information on loading the module):

get_label_angle
get_label_color
get_label_depth
get_label_font
get_label_fontstyle
get_label_halign
get_label_size
get_label_valign

Example 1

chips> add_label(.4, .8, "C_6H_{12}O_6")
chips> print(get_label())
chips> print(get_label("lbl1","font"))

A label is created and becomes current. Calling get_label with no argument returns all the attributes of the object. get_label is called a second time to return just the "font" attribute.

Example 2

chips> add_label(.4, .8, "C_6H_{12}O_6")
chips> add_label(.4, .9, "x_1 * x_1 = x_1^2", "color=green")
chips> print(get_label("lbl1"))

Two labels are created. get_label is called with the id of the first label, returning all attributes.

Example 3

chips> id=ChipsId()
chips> id.label="lbl1"
chips> print(get_label(id))

A ChipsId structure is created and the id.label field is set to "lbl1". get_label is called with the ChipsId.

Example 4

chips> lb = get_label()
chips> print(lb)

Retrieve a structure containing the attribute values of the current label and store the results in "lb". Print the contents of "lb".

Label Preferences and Attributes

The attributes associated with labels are given in the following table, where the "Set?" column refers to whether the attribute can be changed using the set_label() command. To change the label preference settings prepend "label." to the attribute name.

Attribute Description Options Default Set?
angle Angle, in degrees, at which the label is drawn -360.0 to 360.0 0.0 Yes
color Color of the text name or hex; see the Color section of "ahelp chipsopt" default Yes
coordsys coordinate system for the label PIXEL, WINDOW_NORM, FRAME_NORM, PLOT_NORM, DATA see "ahelp coordsys" No
depth Integer value indicating label depth see the Depth section of "ahelp chipsopt" default Yes
font text font helvetica|courier|times|greek; see the Font section of "ahelp chipsopt" helvetica Yes
fontstyle style of the label text normal|bold|italic|bolditalic; see the Font Style section of "ahelp chipsopt" normal Yes
halign Horizontal location of the string reference point of the label auto|base|center|left|right|top; see the Text Alignment section of "ahelp chipsopt" left Yes
size Font size of the text 1 to 100 12 Yes
stem stem used for label id An alpha-numeric character sequence that does not contain a space lbl No
valign Vertical location of the string reference point of the label auto|base|center|left|right|top; see the Text Alignment section of "ahelp chipsopt" base Yes

Bugs

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

See Also

concepts
setget
labels
add_label, current_label, delete_label, display_label, hide_label, move_label, set_label, shuffle_label
utilities
load_font, set_current

Last modified: December 2013
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