Multigraph

This attribute determines whether the legend is present or not; a value of "true" means that the legend should appear, and "false" means that it should not. The default is for the legend to appear if the graph contains more than one plot. You can use this attribute to disable the legend in graphs containing more than one plot, or to enable it in graphs containing only one plot.

These attributes give the location of the legend relative to the plot area, according to the conventions described in the section called “Positioning”. If you think of the legend as being bounded by an imaginary rectangular box, these attributes determine the location of that box. base is the location of the base point relative to the plot area; the default value for base is "1 1" --- i.e. the upper right corner of the plot area. The default for anchor is also "1 1", which means that the upper right corner of the legend is anchored to the base point. position is a coordinate pair of pixel offsets, as described in the section called “Positioning”; its default value is "0 0".

The frame attribute determines whether the legend is positioned relative to the plot area or the padding box (described in the section called “Borders, Margins, and the Plot Area”). More precisely, it determines the coordinate system of the base point, described above. The default value is "plot", which means that the legend will be positioned relative to the plot area. This is usually what you want, since the plot area is where the data is plotted. If you have a graph that has large margins, however, for example to allow for multiple vertical axes, you can specify "padding" for the frame attribute, in which case the legend will be positioned relative to the padding box (which is the entire window minus any border and padding amount).

The legend contains an entry for each plot, layed out in a grid. The rows and columns attributes determine the number of rows and columns in that grid. If you specify one of these values and not the other, the other will be determined by the number of entries in the legend. The default is columns="1" and rows unspecified, which means that the legend will be layed out in a single vertical column, with one row per entry. If you want a single horizontal legend layout instead, specify rows="1" and leave columns unspecified.

The thickness of the border drawn around the legend; the default is "1". Use "0" to turn off the border.

The color of the border; the default is "0x000000", which is black.

The color used to fill the background of the legend; the default is "0xFFFFFF", or white.

The opacity value for the legend, in the range 0.0 to 1.0. This is relevant because depending on where the legend is, it may obscure some parts of the plot data. The default is 1.0, which is completely opaque, which means that any parts of the plot data that appear behind the legend will not be visible at all. any

Determines whether the corners of the legend box, if it is drawn, appear rounded. If cornerradius is 0, which is the default, the corners are drawn square. If cornerradius > 0, then the corners are rounded off using circles whose radius is cornerradius pixels.

An amount of padding, in pixels, to leave between the edges of the legend box and the entries inside it. The default is 0.

The width and height, in pixels, of the icons. The defaults are width="40" and height="30".

The thickness of a border drawn around the icons; the default is "1". Use "0" to turn off the icon borders.

Determines whether the plot is listed in the legend at all. The default behavior is for all plots to have an entry in the legend if the legend is present at all. To omit a particular plot from the legend, specify visible="false" in that plot's legend tag.

The text to be used for the plot's entry in the legend. The default is to use the id of the (first) variable assigned to the plot's vertical axis.