Color Scales

The color scale is a specialized label object that displays a color map and an accompanying numerical scale for color mapped or contour data plots. The color scale displays by default when creating color-filled or gray-scale contour graphs.

1 Adding a color scale to a graph of color mapped data
2 Modifying how scale numbers display
3 Making the color scale display horizontally
4 Editing the Color Scale Control dialog box
5 Manual control of the color scale

Adding a color scale to a graph of color mapped data

Select Graph: New Color Scale.

Right-click in the layer and select New Color Scale.

Click the Add Color Scale button on the Graph toolbar.

These menu commands and the toolbar button are only available if the active data plot is color mapped and a color scale is not already displayed.

Modifying how scale numbers display

The numeric format of the color scale is controlled by the Numeric Formats tab on the Plot Details dialog box (double-click on the graph, or select Format: Plot from the main menu, or select Plot Details from the right-click menu). Here, you will find controls for the following:

Significant Digits
Format	Decimal (1000) Scientific (1E3) Engineering (1k) Decimal (1,000) Note that if you select one of the decimal formats, Origin uses a threshold for conversion to scientific notation. This threshold is controlled on the Numeric Format tab of the Options dialog box (Tools: Options).
Divide by Factor	Divide all the color map and contour levels by some factor.
Decimal Places	Specify either Decimal Places or Significant Digits.
Prefix	Enter a Prefix or a Suffix with which to modify the color map and contour level labels. Prefixes and suffixes display in the graph, but do not display in the level list on the Color Map/Contours tab of the Plot Details dialog box (Format: Plot). When you enter a prefix or suffix, you can use special formatting commands or escape sequences to modify the style of the text (for example, superscript, subscript, and bold).
Suffix

Making the color scale display horizontally

By default, the color scale displays vertically. To display the color scale horizontally, click on the color scale to select it, and then drag a control handle in the horizontal direction.

Further adjustments to the way in which the color scale displays -- i.e. the text font, color bar thickness, etc. -- can be made through the Color Scale Control dialog box (see below).

Editing the Color Scale Control dialog box

To edit the color scale, open the Color Scale Control dialog box:

Double-click on the color scale.

Right-click on the color scale and select Properties from the shortcut menu. This opens the Color Scale Control dialog box.

Text	Specify the text's Font, Color, Size, and Style (Bold, Italic or Underline).
Background	Select the desired background from this drop-down list.
Reverse Order	Select this check box to reverse the color map and associated text's level order.
Color bar thickness	Set the width of the color scale (% of font point size).
Label gap	Set the gap between the color scale and its associated labels (% of font point size).
Label side offset	To shift the labels up and down in relation to the color scale, edit the Label side offset combination box. Negative values move the labels up in relation to the color scale, while positive values move the labels down (units are in % of font point size).
Labels	This group is used to set how to show the labels. Show on Major Levels Show the labels on major levels. Increment If your color scale has a large number of levels, the level labels may overlap and be difficult to read, if you try to display all of them, and you may wish to periodically skip a certain increment of levels between adjacent labels. To do this, select or type the desired increment in this combination box. For example, to display every third label, select 3 from this combination box.

Manual control of the color scale

Display of a customized color scale object can be controlled manually with the \l(CN) switch. In this switch, C must be capitalized, and N is an integer representing a level. The color of the level is the same as the color set in the Color Map/Contours tab of the Plot Details dialog.

To control the color scale manually:

Create a text object by clicking the Text Tool button on the Tools bar.
Enter arbitrary characters, and then select this text object and bring up the Object Properties dialog by selecting Properties from the right-click menu.
In the Object Properties dialog, change the characters to be \l(CN), then a level's color, specified by N, is shown in the lowest panel.
Click the OK button; the specified level is shown on the graph.

If N is 0, 1, or not specified, the color is black. If N=2, the color for missing values will be shown. If N is larger than 2, the color for the (N-2)th level will be shown. If N is beyond 2 more than the total number of all levels, the color shown on the color scale is out of control.

Vertical color scale

To create a vertical color scale, enter one \l(CN), then start a new line and enter another \l(CN). Repeat the above operations until all the levels are finished. To eliminate the space between two levels, set Line Spacing in the Text Fonts tab of the Options dialog (Origin menu Tools: Options) to be 0.

Horizontal color scale

To create a horizontal color scale, enter \l(CN) in one line.