To change a polar plot’s format:
• Click in the polar plot to select it.
• Double-click in the polar plot. Alternatively, choose Graphee-Polar Plot from the Format menu. You’ll see the dialog box for formatting polar plots, shown below.
• If necessary, click the Polar Axes tab.
• There is a complete group of settings for each axis. Change the appropriate settings.
• Click “OK” to accept your changes and close the dialog box. Mathcad redraws the polar plot with the new settings in effect. Alternatively, click “Apply” to see the plot redrawn without closing the dialog box
Each axis has the following settings associated with it:
When this box is checked, the radial axis is logarithmic. Axis limits must be positi ve. This setting is available only for the radial axis. Figure 21-10 on page 513 illustrates a polar plot with a logarithmic axis.
When this box is checked, the tick marks on the selected axis are replaced by grid lines. If the axis is logarithmic, then logarithmically spaced grid lines are added if space permits. Radial grid lines are circles of fixed radius; angular grid lines radiate out from the origin at a fixed angle. Figure 21-8 on page 512 compares a plot with tick marks to the same plot with grid lines.
When this box is checked, the selected grid lines are numbered. Figure 21-8 on page 512 illustrates numbers being used with grid lines.
When this box is checked, you can add reference lines to your polar plot. See “Adding radial reference lines”
When this box is checked, Mathcad automatically selects the number of grid markings (tick marks or grid lines). When the box is unchecked, you choose the number of grid markings (from 2 to 99) by typing a number in the No. of Grids text box. You can specify the number of grid markings only when Log Scale is unchecked. Figure 21-9 on page 512 illustrates the effect of Auto Grid. In addition to these check boxes, the dialog boxes contain the following:
No. of Grids .
When available, this text box indicates the number of tick marks or grid lines on the associated axis. You can enter a number between 2 and 99, inclusive. This box is only available when Auto Grid and Log Scale are unchecked. Figure 21-9 on page 512 shows the effects of defining the number of grid lines on both the radial and the angular axes.
These buttons let you choose between crossed axes, no axes at all, and a plot enclosed by a circle (perimeter). Figure 21-11 on page 513 illustrates the difference between perimeter and crossed axes.
See the section “Setting default formats” below to learn how to:
• Quickly restore a polar plot to its default format settings.
• Use a particular plot as a model for all future polar plots.