You'd like to embellish your charts with annotations (for example, to add emphasis or provide notes for viewers of your charts).
The callouts (text boxes with arrows) on the chart shown in Figure 4-16 in Recipe 4.8 were added using Excel's drawing tools. You need to display the Drawing toolbar if it isn't already visible. Select View → Toolbars → Drawing from the main menu bar. Figure 4-16 shows the Drawing toolbar docked in the lower left of Excel's window.
The drawing toolbar contains all sorts of tools, allowing you to add text notes, callouts, arrows, shapes, and many other elements to your charts. There are also tools that allow you to format your annotations. For example, you can edit line style and thickness, color, and fill pattern, among other attributes. The 3D style buttons even allow you to create 3D effects to really make your annotations stand out. There are also tools that allow you to change the depth order, spacing, and alignment of your annotations.
To draw on your chart, simply select your chart and then click on the desired element from the drawing toolbar. Now start drawing on your chart. For example, to add a line to your chart, click the chart, then click the line button on the drawing toolbar, then click and drag on your chart to add the line. You can change the position of the line after it has been drawn by clicking and dragging it. You can also edit the line endpoints by clicking and dragging the endpoint handles (little circles).
By the way, you can use these same drawing tools directly on your spreadsheets; they aren't limited to drawing on charts. Follow the same procedure described in this recipe for drawing on charts, but instead just draw directly on your spreadsheet.
Figure 4-29 shows an example chart that I embellished using Excel's drawing tools.
This chart illustrates results of a standard beam analysis. The results include load, shear, and bending moment curves, as well as calculated reactions at each support. To create this chart, I prepared a table of data including the load, shear, and bending moment values at various locations along the beam. I plotted this data on a standard XY scatter chart using the procedure outlined in Recipe 4.1. I formatted the primary and secondary axes to display specific ranges with minimum and maximum units, as described in Recipe 4.4. For the primary y-axis, I specified the crossing point for the x-axis as -800. I did this to force the x-axis toward the bottom of the chart.
After setting up the curves and axes, I labeled the bending moment and shear curves using Callout text boxes with leader arrows, which are accessible from the Drawing toolbar's Autoshapes → Callouts menu. To represent the beam, I added a basic rectangle shape and manually positioned it where the y-axis values show zero. I formatted the rectangle using a cross-hatched fill pattern.
Right-click on any drawing element you add to a chart or spreadsheet and select Format Autoshape from the menu to format the shape (or press Ctrl-1). You can also using the formatting tools displayed on the Drawing toolbar.
I used small triangle shapes to represent standard, simple supports for the beam. I added these by accessing the Autoshapes → Basic Shapes menu from the Drawing toolbar. I manually positioned them at the proper x-location using the mouse. For the reaction forces, I added a couple of arrows from the Autoshapes → Block Arrows menu on the Drawing toolbar. I formatted these with a red fill color. Further, I added a couple of text boxes (also accessible from the Drawing toolbar) to indicate the calculated reaction forces. I formatted the beam, support, and reaction shapes with a faint drop shadow for a little depth effect. I used the Shadow Style tool (the button with a rectangle and drop shadow, second from the right) from the Drawing toolbar to format the drop shadow.
These are just a few examples of the sort of embellishments you can add to your technical charts to make them more meaningful, readable, and attractive. Excel's drawing tools are far more extensive than has been demonstrated here. You can add 3D text and shapes, draw smooth lines and edit their points, and prepare flow charts, among many other drawing tasks. I encourage you to explore the drawing tools more.