Mathcad provides several ways to help you to identify what it is that you’ve plotted.

You can choose to display:

• A title, either above or below the graph.
• Axis labels to describe what’s plotted on each axis.
• Legends to identify the individual traces.
• Arguments showing what you typed into the x- and y-axis place holders.

Figure 20-13 shows the relative locations of each of these types of labels on a boxed axes graph and on a crossed axes graph

You can use these labels all together or in any combination. By default, Mathcad shows neither title nor axis labels, displays the arguments, and hides legends

Working with titles

To add a title to a graph, follow these steps:

• Click in the graph to select it
• Choose Graph~X- Y Plot from the Format menu or double-click on the selected graph. Mathcad displays the dialog box for formatting X-Y graphs. If necessary, click on the Labels tab.

• Type a title for your graph into the Title text box.
• Click on either the Above or Below button, depending upon where you want to put the title. Note, however, that Mathcad doesn’t display the title until you click “Apply” or close the dialog box.

• Make sure that the Show Title check box is checked, If it isn’t, Mathcad still remembers the title but won’t display it

• Click “OK” to accept your changes. Mathcad redraws the graph with the title in place. Alternatively, click “Apply” to preview your title without closing the dialog box.

Labeling axes on a graph

You can also label one or both axes of a graph in much the same way as you add a title to a graph. The x-axis label appears directly below the x-axis, and the y-axis label appears just to the left of the y-axis. To label an axis, follow these steps:

• Click in the graph to select it.
• Choose GrapheeX> Y Plot from the Format menu or double-click on the selected graph. Mathcad displays the dialog box for formatting X-Y graphs. If necessary, click on the Labels tab to see that page, as shown in the preceding section.
• Type the axis labels into the appropriate text boxes.
• To save the label name without having it appear on the graph, click X-Axis or YAxis to remove the check.
• Click “OK” to accept your changes and close the dialog box. Mathcad redraws the graph with the new settings in effect. Alternatively, click “Apply” to preview your changes without closing the dialog box. To edit an axis label, follow these steps:
• Click in the graph to select it.
• Choose Graph~X-Y Plot from the Format menu or double-click on the selected graph. Mathcad displays the dialog box for formatting X-Y graphs. If necessary,
• Edit the information for the title as appropriate.
• To remove a label, delete it from the text box.
• Click “OK” to close the dialog box.

Displaying or hiding arguments and legends

Mathcad provides both arguments and legends for identifying specific traces on a graph:

• Arguments are the expressions that you typed into the placeholders of the x- and yaxes to create the graph. By default, Mathcad displays arguments.
• Legends are labels that appear underneath the graph containing a name and an example of the line and symbols used to draw the trace. By default, legends are hidden.

To display or hide arguments and legends:

• Click on the graph to select it.
• Choose Graph::::}X-Y Plot from the Format menu or double-click on the graph. Mathcad displays the dialog box for formatting X-Y graphs, as shown below. If necessary, click on the Traces tab.
• To suppress the display of the arguments, click on Hide Arguments to add a check.
• To show the legend, click on Hide Legend to remove the check.

Modifying your graph’s perspective

Mathcad provides options for manipulating the presentation of your graph:

• You can resize the graph, making it proportionally larger or smaller or stretching the x-axis or y-axis for emphasis.
• You can zoom in on a portion of the graph.
• You can get the coordinates for any point that was plotted to construct the graph.
• You can get the coordinates for any location within the graph.

The rest of this section shows how to use these features.

Resizing a graph

Resizing a graph is very much like resizing a window:

• Click in the graph to select it.
•Move the mouse pointer to one of the three handles along the edge of the graph.

The pointer will change to a double-headed arrow.

• Press and hold down the mouse button and move the mouse in the direction that you want the graph’s dimension to change.
• Once the graph is the right size, let go of the mouse button.
• Click outside the graph to deselect it.

Note that when you change the size of a graph for which the Auto Grid is set, Mathcad may add or delete tick marks or grid lines or change axis limits to maintain the default spacing.

Zooming in on a graph

Mathcad allows you to select a region of a graph and magnify it. To zoom in on a portion of a graph, follow these steps:

• Click in the graph to select it.
• Choose Graph-e Zoom from the Format menu, or click on the Zoom button on the Graph Palette. The X-Y Zoom dialog box appears

• If necessary, reposition the X-Y Zoom dialog box so that you can see the entire region of the graph you want to zoom.
• In the graph region, click the mouse at one corner of the region you want to magnify.
• Press and hold down the mouse button and drag the mouse. A dashed selection rectangle emerges from the anchor point.
• When the selection rectangle just encloses the region you want to magnify, let go of the mouse button. If necessary, you can click on the selection rectangle, hold the mouse button down, and move the rectangle to another part of the graph.
• The coordinates of the selected region are listed in the Min: and Max: text boxes of the X-Y Zoom dialog box. Click the “Zoom” button to redraw the graph. The axis limits are temporarily set to the coordinates specified in the X-Y Zoom dialog box. To make these axis limits permanent, click “Accept.”

Before you make these axis limits permanent, you can select another region to zoom by enclosing another selection rectangle around a new region. Press “Un zoom” to undo the zoom you’ve just made. If you’re working with a graph that has already been zoomed, you may want to view the original graph as it was before any zooming took place. To do so, click on “Full View.”

Getting a readout of graph coordinates

To ee a readout of graph coordinates of the specific points that make up a trace, follow these steps:

• Click in the graph to select it.
• Choose Graphee’Trace from the Format menu, or click on the

Trace button on the Graph Palette, to show the X-Y Trace dialog box

• If necessary, reposition the X-Y Trace dialog box so that you can see the entire region of the graph. Note that the Track Data Points check box is checked.
• In the graph region, click and drag the mouse along the trace whose coordinates you want to see. A dotted cross hair jumps from one point to the next as you move the pointer along the trace.
• If you release the mouse button, you can now use the left and right arrows to move to the previous and next data points. Use the up and down arrows to move to other traces.
• As the pointer reaches each point on the trace, Mathcad displays the x and y values of that point in the X-Value and Y-Value boxes.
• The x and y values of the last point selected are shown in the X-Value and Y-Value boxes. The crosshair remains until you click outside the graph.

To copy a coordinate to the clipboard:

• Click “Copy X” or “Copy Y”. You can then paste that value into a math region or a text region on your Mathcad worksheet, into a spreadsheet, or into any other application that allows pasting from the clipboard.
• Double-click on the control box in the upper-left-hand corner to close the X-Y Trace dialog box. The crosshair will remain on your graph until you click anywhere outside the graph or click the “Close” button.

To see a readout of graph coordinates for any location in a graph:

• Follow the above procedures to call up the X-Y Trace dialog box.
• Click on Track Data Points to uncheck it.
• In the graph region, click and drag the mouse pointer over the points whose coordinates you want to see. A dotted crosshair follows the pointer as you drag it over the graph. Mathcad displays the coordinates of the pointer in the X-Value and Y-Value boxes. Thex and y values change continuously to reflect the current pointer
position.
• When you release the mouse button, the X-Value and Y-Value boxes show the x and y values of the last pixel selected.

Gallery of graphs