Contour Plot Platform Options

Using the options in the red triangle menu next to Contour Plot, you can tailor the appearance of your contour plot and save information about its construction.

Descriptions of Contour Plot Platform Options
Show Data Points	Shows or hides (x, y) points. The points are hidden by default.
Show Missing Data Points	Shows or hides points with missing y values. Only available if Show Data Points is selected.
Show Contours	Shows or hides the contour lines or fills. The contour lines are shown by default.
Show Boundary	Shows or hides the boundary of the total contour area. The boundary is shown by default.
Show Control Panel	Shows or hides the Alpha slider that allows you to change the Alpha shapes filter.
Transform	If the contour plot includes a Color role, the Transform option is enabled. See Example of Triangulation, Transform, and Alpha Shapes for details. None The triangulation is computed without any scaling to coordinates using Delaunay triangulation. Delaunay triangles are computed to maximize the minimum angle of the triangles in the triangulation. This value is selected by default. Range Normalized The X1/X2 values are both scaled to [0,1] prior to computing the triangulation. If the X1/X2 limits are different, then this is a non-uniform scale. This option may be more desirable in cases where the X1/X2 units are very different.
Fill Areas	Fills the areas between the contours with a solid color. It is the same option that is available in the Launch window. If you leave it deselected in the Launch window, you can see the line contours before filling the areas. See Fill Areas.
Label Contours	Shows or hides the label (z-value) of the contour lines.
Color Theme	Select another color theme for the contours.
Reverse Colors	Reverses the order of the colors assigned to the contour levels.
Change Contours	Set your own number of levels and level increments. See Contour Specification.
Save	This menu has options to save information about contours, triangulation, and grid coordinates to data tables. See Contour Plot Save Options.
Script	This menu contains commands that are available to all platforms. They enable you to redo the analysis or save the JSL commands for the analysis to a window or a file. For more information, see Using JMP.

Fill Areas

If you select Fill Areas, the areas between contour lines are filled with the contour line colors. This option is available in the Launch window and in the red triangle menu for Contour Plot. Comparison of Contour Lines and Area Fills shows a plot with contour lines on the left and a plot with the contour areas filled on the right.

Comparison of Contour Lines and Area Fills

Areas are filled from low to high values. An additional color is added in the filled contour plot for the level above the last, and highest, contour line.

Contour Specification

If you do not select options in the Launch window, the default plot spaces the contour levels equally within the range of the Y variable. The default colors are assigned via the Continuous Color Theme in Preferences. You can see the colors palette with the Colors command in the Rows menu or by right-clicking on an item in the Contour Plot legend.

You can specify contour levels either in the Launch window (the Specify button) or in the report window from the red triangle menu for Contour Plot (the Specify Contours option).

Example of Contour Specification: Launch Window (on the left) and Menu (on the right)

Specify

This option is both in the Launch window and on the red triangle menu for Contour Plot (the Specify Contours option).

Selecting this option displays the Contour Specification window. See The Contour Specification Window. Using this window, you can do the following:

•	change the number of contours

•	specify minimum and maximum values to define the range of the response to be used in the plot

•	change the increment between contour values

You supply any three of the four values, and the remaining value is computed for you. Click on the check box to deselect one of the numbers and automatically select the remaining check box.

The Contour Specification Window

Colors are automatically assigned and are determined by the number of levels in the plot. After the plot appears, you can right-click (press CONTROL and click on the Macintosh) on any contour in the plot legend and choose from the JMP color palette to change that contour color.

Retrieve

This option is both in the Launch window (the Retrieve button) and on the red triangle menu for Contour Plot (the Retrieve Contours option).

Note: Neither the button nor the menu option are active unless there is an open data table in addition to the table that has the contour plotting values. When you click Retrieve or select Retrieve Contours, a window with a list of open data tables appears.

Using this option, you can retrieve the following from an open JMP data table:

•	the number of contours

•	an exact value for each level

•	a color for each level

From the list of open data tables, select the data table that contains the contour levels.

For level value specification, the Contour Plot platform looks for a numeric column with the same name as the response column that you specified in the Launch window. The number of rows in the data table defines the number of levels.

If there is a row state column with color information, those colors are used for the contour levels. Otherwise, the default platform colors are used.

Revert Contours

This option appears only on the red triangle menu for Contour Plot.

If you have specified your own contours, selecting this option reverts your Contour Plot back to the default contours.

Contour Plot Save Options

This menu has options to save information about contours, triangulation, and grid coordinates to data tables.

Save Contours creates a new JMP data table with columns for the following:

•	the x- and y-coordinate values generated by the Contour platform for each contour

•	the response computed for each coordinate set

•	the curve number for each coordinate set

The number of observations in this table depends on the number of contours you specified. You can use the coordinates and response values to look at the data with other JMP platforms. For example, you can use the Scatterplot 3D platform to get a three-dimensional view of the pond.

Generate Grid displays a window that prompts you for the grid size that you want. When you click OK, the Contour platform creates a new JMP data table with the following:

•	the number of grid coordinates you requested

•	the contour values for the grid points computed from a linear interpolation

Save Triangulation creates a new JMP data table that lists coordinates of each triangle used to construct the contours. By default, JMP uses Delaunay triangulation to connect the nearest data points to form triangles. The resulting set of triangles are calculated so that no other data points are inside a triangle’s circumscribed circle, that is, the circle that passes through the three vertices of the triangle. To change the triangulation to a normalized scale, select Transform > Range Normalized.

Use Formulas for Specifying Contours

Most often you construct a contour plot for a table of recorded response values such as the Little Pond data table. In that case, in the launch window, Use Table Data is checked and the Specify Grid button is unavailable. However, if a column has a formula and you specify that column as the response (Y), the Specify Grid button becomes active.

When you click Specify Grid, the window shown in Example of the Contour Specification for Formula Column appears.

Example of the Contour Specification for Formula Column

You can complete the Specify Grid window and define the contour grid in any way, regardless of the rows in the existing data table. This feature is also available with table templates that have one or more columns defined by formulas but no rows.