Within the ViewPlan tool, EE has the capability to plot 2D contour lines for any simulated parameters at any time steps. The contour option is enabled by selecting the Contour check box in the Viewing Options form. Beside the check box is a button to open the Contour Control Form which contains two tabs such as Formatting and Contour Intervals as shown in Figure 1

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Figure 1 ViewPlan: Contour View.


Figure 2 ViewPlan: Contour Control Form – Formatting.

Formatting Tab

Formatting tab provides numerous formatting options as shown in Figure 2. The Labels frame provides a check box to switch on or off the labels and a text box for entering the spacing between the labels. The style and font of the labels may also be edited with the Text Properties button. In addition the background and foreground colors, label position and label precision may also be modified.

The Data Points frame allows display of symbols at the cell corners and editing of the symbol properties with the adjacent button. The user may also display values of the parameter currently being viewed with the Show Values check box. The font and position of the labels may be edited with the adjacent button.

The Precision frame provides two options for the numerical precision of the contour labels, floating or fixed. If Float is selected the precision value is ignored. Only if the Fixed button is selected is the label displayed to the numerical precision entered in the text box.

Contour Color Fill Options provide the capacity to "flood fill," that is to fill the space between contours with the color based on the legend color ramp. It is recommended that when using contours the user should apply flood fill as it provides a constant color over the midpoint of the contour intervals. Note however, that this option overrides the Outline Only" option in the Labels tab. The Reverse Colors check box reverses the color ramp in the legend.

The Lines frame provides various options for editing the contour lines. Lines may be toggled on and off with the Show Lines check box. The color of the contour from the color ramp is toggled on and off with the Contour Color check box. For both the major (labeled) and minor (unlabeled) lines, line thickness, color and style may be edited with the Line Properties button.

Contour Intervals Tab

The contour internals tab is shown in Figure 3 below. The From the Data frame displays upper and lower limits for the parameter selected for the user's information. The contour tool assumes the minimum and maximum contour interval from this data and automatically sets the number of contours to 11, basing the major interval on this. The minor interval is set by default as one third of the major interval. Adjusting the minor interval will recalculate the major interval and number of contours accordingly. Modifying the number of contours will recalculate the major and minor interval values.

The Clip Range button will clip all contours outside the max and min contour values defined by the user.

The View Options frame provides two options for methods of calculating the contours: based on the corners of the cell, or on the cell centroid. The Searching Radius text box tells EE what radius of cells should be used in the calculation of the contours. The Use Spline check box will employ a spline function for calculation of the contour line. The number of points to be used in the spline calculation is user defined.
The Outline Only checkbox will turn off the legend and background colors and display only the contour lines. Note that this will not be visible if Flood Fill has been selected.

Figure 3 ViewPlan: Contour Control – Limits