3.9.12 Legend Substitution Notation

Legend-Substitution-Notation

Origin Graph Legends

There are four standard legends for Origin graphs:

The Data Plot Legend	The Categorical Values Legend	The Box Chart Components Legend	The Point-by-Point Legend

• Data Plot Legend: The default legend for most 2D and 3D graphs combines a plot symbol with legend text derived from column metadata (e.g. column Long Name).
• Categorical Values Legend: Legend entries combine a plot symbol -- one for each category within a column of worksheet data -- with the text that names the category. Categorical legends can depict multiple categorical variables (multiple columns of categorical data), with symbol variations listed by categorical variable.
• Box Chart Components Legend: Legend entries typically combine a plot symbol with a column metadata or category label, plus a symbolic list of displayed statistics.
• Point-by-Point Legend: A legend that combines a plot symbol with a number (the number can be a plot index number or a data value). Since every data point generates a legend entry, this legend type is most suited to certain plot types (e.g. Piper Diagrams) and small datasets.

The following information is presented to help you understand the variable syntax behind the various legends and, when necessary, to help you to modify legend object content.

Data Plot Legend (most 2D and 3D graphs)

For most 2D and 3D graphs, the legend is constructed using the following substitution syntax:

Plot Symbol Component: \L([LayerIndex.]PlotIndex[,PointIndex[,option]])
Text Component: %(LayerIndex.PlotIndex[Axis, @option])

This can be seen in the user interface when you right-click on a selected legend object and choose Properties:

Two things to note:

• The symbol component is enclosed by \L() and the text component is enclosed by %().
• Square brackets in the syntax model merely indicate an optional argument; you do not need to type the square bracket.

Plot Symbol Component

This notation is used to construct the legend's data plot symbol, by displaying the symbol of the specified data plot. LayerIndex is optional but if omitted, the active layer is assumed. Additionally, the optional PointIndex is used to display the symbol assigned to a special data point.

Basic Syntax:

\L([LayerIndex.]PlotIndex[,PointIndex[,Option]])

where...

• LayerIndex(optional): The layer of the specified data plot, indexed from 1. For the active layer, this option can be omitted, as in \L(PlotIndex).
• PlotIndex: The data plot's position (indexed from 1) in the data list at the bottom of the Data menu or in Layer Contents. Note: this list is for all plots in the active graph layer.
• PointIndex(optional): If a single point in a dataplot has been customized, this option is used to display the single point's symbol.
• Option: Normally, the plot symbol is the representation of 1st point of the the specified data plot in specified layer(e.g. a scatter symbol) or is a representation of the data plot (e.g. line for line graph) and is generated. Or if PointIndex is specified, then it's the representation of the specified point. However, the legend data plot symbol can be customized to display independently of the data plot, as shown in the following Examples. If needed, a plot symbol can be generated that is completely independent of graph window data plots (symbol, line + symbol, and line types). See this section for details.

Legend of Partial Property of Symbol

Legend Entry	Description	Example
\l(1) %(1)	Original line+symbol plot
\l(1, style:s) %(1)	Show symbol only for a line + symbol plot
\l(1, style:l) %(1)	Show line only for a line + symbol plot
\l(1, style:sls)	Show legend as symbol - line- symbol for a line + symbol plot

Legend of Scaled Symbols

Legend Entry	Description	Example
\l(1) %(1)	Original line+symbol plot
\l(1, size:5) %(1)	Show symbol size 5
\l(1, size:p150) %(1)	Scale symbol size as 150% of original symbol size
\l(1, LineWidth:3) %(1)	Show line width as 3
\l(1, LineWidth:p1000) %(1)	Show line width as 1000% of original line width
\l(1, Length:p50) %(1)	Show line length as 50% of original length
\l(1) %(1)	Original column plot
\l(1, PatternHeight:p50) %(1)	Show bar height as 50% of original height
\l(1, PatternWidth:p50) %(1)	Show bar width as 50% of original width

Legend of Bar Elements

Legend Entry	Description	Example
\l(1) Bar	Original bar plot (1st bar of 1st layer)
\l(1, style:C) Fill Color	Show fill color of Bar
\l(1, 1, 2) Fill Color	Show fill color of the 1st bar of 1st layer in a block
\l(1, style:P) Pattern	Show Pattern Style of Bar
\l(1, style:P#81F7F3) Custom Fill Color	Show legend of fill with custom color
\l(1, 1, 1) Border Color	Show border color of the 1st bar of 1st layer in a block
\l(1, 1, 3) Pattern Color	Show pattern color of the 1st bar of 1st layer in a block

It is possible to add symbol, line + symbol and line-type plot symbols that are not associated with any plot in the layer, to the legend. For information on this, see Adding Symbols Not Used in Plots.

Text Component

Legend text can be created using literal text (manually) but the more usual and efficient method relies on substitution notation -- use of LabTalk variables to display metadata associated with the dataplot. These metadata can be accessed by specifying an "@" option and can be used to override default legend construction behavior specified in the Legends/Titles tab in the graph's Plot Details dialog box. As previously mentioned, square brackets denote optional arguments and are not typed when constructing the legend text.

Basic Syntax

%([LayerIndex.]PlotIndex[Axis[, @option]])

where...

• LayerIndex(optional): The layer of the specified data plot, indexed from 1. For the active layer, this option can be omitted, as in \L(PlotIndex).
• PlotIndex: The data plot's position (indexed from 1) in the data list at the bottom of the Data menu or in Layer Contents. Note: this list is for all plots in the active graph layer.
• Axis: For the specified layer and plot, X, Y or Z, indicates which column of the source data will be referred to. If not specified (default), it is assumed to be Y for 2D graphs, and Z for 3D graphs.
• @option: This option can be used to override the default Auto Legend Translation Mode that is saved with the graph template. See the Legend Text Customization section of this page for a list of @options related to graph legends.

Examples

Notes:

• Any text object can contain this syntax and act like a legend provided the Link to (%, $) Substitution Level on the object properties Programming tab is set to 1.
• The active layer for any legend object is the layer to which the object is attached.
• Only one object named Legend can exist in any one layer.

Categorical Values Legend

In Origin, each text "value" in a categorical dataset is mapped to an index value, starting from 1, to allow for plotting and analysis operations. Since this index value controls such things as plotting order, you can order your categorical values in any way that suits you.

As with the standard Data Plot Legend, Origin employs a special syntax to control how plot symbols and text are displayed in the Categorical Values Legend. Graphs must meet certain requirements in order to support this specialized legend type. Refer to the plot requirements for details.

Plot Symbol Component: \L(PlotIndex[.DataPoint], mCategoryIndex, PlotElement)
Text Component: %(PlotIndex, mCategoryIndex, PlotElement)

One thing to note:

• The syntax is similar to the standard legend but includes a literal m in the second argument for both the plot symbol and text components.

Plot Symbol and Text Components

Basic Syntax

\L(PlotIndex[.DataPoint], mCategoryIndex, PlotElement) %(PlotIndex, mCategoryIndex, PlotElement)

where...

• PlotIndex: An integer which indicates plot order (seen in Plot Details or the Data list).
• DataPoint: An integer which is the data point row index.
• CategoryIndex: The index number for a particular categorical value (determined by column Sort status).
• PlotElement: An integer representing the plot element that is indexed to the categories within a dataset. The parameter can take values of 1 to 14, where 1=edge color, 2=fill color, 3=pattern color, 4=symbol shape, 5=symbol interior, 6=symbol size, 7=line style, 8=fill pattern, 9=box chart connect lines, 10=vector color, 11=vector style, 12=line style, 13=line width, 14=violin plot fill color. With the exception of pattern color (defined in the Pattern tab), all plot elements are controlled in the Symbol tab of the plot. All values may not be valid for a particular plot style. When this is the case, an invalid entry will be indicated by a red x in a red box or a hollow black square.

Each plot element generates a legend entry that combines the plot element with a dataset identifier derived from column metadata. In the above example, for PlotElement = Symbol Color (edge color), that identifier is "Gender". This identifier is determined by the "@option" chosen from the list below. The remainder of the notation that generates the text "Gender" merely identifies the book and column used in indexing PlotElement and is not intended to be modified.

Examples:

The Box Chart Components Legend

Like other legend types, the legend for box chart components is comprised of a symbol component and a text component. However, the syntax is unique to the box chart legend.

Plot Symbol Component

\L(PlotIndex,ComponentChar)

Text Component

%(PlotIndex, @V"Box_ComponentChar")

Values of ComponentChar

• PlotIndex: An integer which defines the data plot number.
• ComponentChar: One or more characters to define a component of the box chart. Note how in Text Substitution, the characters are preceded with Box_ and enclosed in double quotes.

Point-by-Point Legend

The Point-by-Point Legend generates a legend entry for every plotted data point.

Graphs must meet certain requirements in order to support this specialized legend type. Refer to the plot requirements for details. The Point-by-Point legend is the default legend type for Piper diagrams.

Like other legends, the Point-by-Point legend syntax has a plot symbol component and a text component.

Basic Syntax

\L([LayerIndex.]PlotIndex[,PointIndex]) %([LayerIndex.]PlotIndex[, @option])

The "@options" typically used in Point-by-Point legends are those for worksheet cell access, specifically the @V and @WT options. See Worksheet Cell Access for information.

Legend Text Customization

The legend text is generated by %( ) substitution notation that incorporates dataset metadata stored in the worksheet column. By default, the graph template uses the Auto Legend setting that is saved with the worksheet template. You can override this default construction using the following list of "@options".

Basic Syntax

See discussions of individual legend types above for use of @options variables.

Using the Data Plot Legend common to most 2D and 3D graphs as an example ...

%([LayerIndex.]PlotIndex[Axis] [,@option])

• If symbol color or size is defined by a dataset, then PlotIndex can be replaced with a special syntax that refers to the modifying dataset: for color mapping/indexing use ?R, for size indexing use ?S.

For example, use %(1S,@LL) will show 1st plot's Size dataset's column's Long name.

For example, use %(1.2R,@LL) will show 1st layer's 2nd plot's color dataset's column's Long name.

• You can combine multiple @options interspersed with arbitrary text using something like the following syntax:

%(PlotIndex,@(@option1+@option2+...))

For example, using the expression %(1,@(@LL(@LU))), will combine Long Name and Units in the form of Long Name(Units).

• Within the inner parentheses you can mix arbitrary text as in:

%(1X,@(Long Name @LL, Units @LU, Comments @LC))

List of @Options

Below are some frequently used @options for customizing graph legend text. While many of these "@" label options can only apply to workbook data, some of them are applicable to matrix data, as well, for example:

%(1,@W) // returns the matrixbook short name.

Examples in the following table refer to the above figure:

• Note that system parameters are always named as Parameters, Parameters 2, etc. whereas user-defined parameters can have assigned names such as UserDefined, UserDefined1 or custom names such as No. of points, Sample, etc.
• The plot portion of the syntax can refer to the plot by number (e.g. "1") or using the "?" wildcard which refers to label row cells in the same column as the plot data.

Worksheet Cell Access

There are several special @options for returning worksheet cell content. The @V and @WT options are used mostly for the point-by-point legend:

Adding Symbols Not Used in Plots

As mentioned, the legend entry is composed of a plot symbol component and a text component. Typically, a legend plot symbol is used by one of the data plots in the graph window. However, it may happen that you want to add a legend plot symbol that is not used by any plot in the graph and that is the subject of this section.

Options for Constructing Symbol, Line + Symbol, Line

Beginning with Origin 2018, you can use the legend object's Text tab controls (Properties > Text tab > Add Legend Symbol button) to manually add custom plot symbols of the type used in symbol (scatter), line + symbol and line plots.

Whereas, previously you were required to manually build such symbols using a complex syntax, you can now simply construct plot symbols using the user-interface dialog box. When you do so, you will simultaneously generate the syntax used to construct the symbol. Thus, the user-interface is likely the easiest way to obtain strings for generating custom symbols.

Examples: Note that properties can be combined in a comma-separated list.

\L(O Shape:Star, Interior:Open, Style:s, Fill:3, EdgeColor:4, Size:15.0, EdgeWidth:20.0)
\L(O LineStyle:Dash, ArrowShape:Stealth, BeginArrowShape:Diamond, Style:L, LineColor:2, ArrowWidth:7.0, ArrowLength:10.0,
     BeginArrowWidth:8.0, BeginArrowLength:12.0)
\L(O Shape:Circle, Interior:Open, LineStyle:Solid, Fill:2, EdgeColor:5, Size:14, EdgeWidth:15.0, LineColor:5, Gap:60)

Options for Constructing Blocks

The following table explains the syntax used in constructing block-style plot symbols.

There are a couple of important differences with the syntax used for line, line + symbol and line-style plot symbols.

• The \L(O syntax is not supported by this style of plot symbol. Instead the user must use an \L(1, syntax.
• The \L(1, syntax cannot create a symbol without a parent data plot. Whereas with the \L(O syntax, one can add symbols to a legend object in an empty graph window, the \L(1, syntax must begin with an existing data plot of the appropriate type (i.e. a plot which uses a Pattern tab in Plot Details, such as a column plot). Hence, any symbol that you add to the legend is really a modification of an existing plot symbol, not an entirely new one.
• While the \L(O syntax uses a comma-separated list, the \L(1, syntax uses a space-separated list.

Examples: Note that properties can be combined in a space-separated list.

\L(1, PatternScale:p200 PatternFill:2 BorderStyle:Dash BorderColor:4 BorderThick:2 Width:40 Height:40)

Old Syntax for Adding Symbols Not Used in Plots (v2017 and earlier)

While it requires some patience, you can create a legend symbol with no relationship to plotted data.

The following four kinds of syntax can be used in different occasions, depending on what kind of symbols you would like to use.

Note: When using the \L(S ) syntax, defining the first variable as 0 means to use an Origin built-in symbol, and defining it as 1 means to use a user-defined symbol or an ASCII character.

The definition of each variable is listed below:

When one variable is left as empty, the default value will be used for this variable. The syntax \L(O SymEdgeColor,Sym,Fill,) will use the default value for all variables after Fill. You can also use these worksheet cell access notations to define one of the variables using a worksheet cell value.

A simpler syntax is available to create a Line Legend Symbol.

\L(L Color, Thickness, Style)

Other Legend Customizations

Special Formatting of Legend Text

You can also customize the text format by escape sequences. Several frequently used examples are provided below:

Legend Element Alignment

To specify the alignment properties for symbol and text in legend, you need to activate the graph, and run the script below in Script Window:

legend.align=1;   //turn on the alignment mode

Then, you can right click the legend to select Properties to open the dialog, and add \^() as cell anchor, which set alignment for the object on the right side of anchor, \^(l), \^(c), \^(r) are LEFT, CENTER and RIGHT alignment respectively, for example:

After clicking OK, the legend will be shown the same as the preview in dialog.

Alternatively, you can press Ctrl and drag to re-arrange the legend:

For instance, you can make a legend object at the right side of current legend row when using Ctrl+drag. In this case, you need to use \^(lu), \^(cc), \^(ru) instead \^(l), \^(c), \^(r) between symbol and text:

In this way, the legend items of plots and special points will be treated as one group when Ctrl+drag rearranging, as shown below:

Otherwise, the symbols and corresponding texts will be separated when Ctrl+drag rearranging: