To add a line of constant value using a function plot, you can use these steps:
- Click anywhere on the existing graph to select it.
- Click the Graphs | Add to Graph | Plot command ().
- In the Select Plot Type dialog, select Function Plot and click OK.
- In the Choose Axes dialog, select the axes to use for the new constant value line and click OK. The plot is added using the default options.
- Click on the Function Plot in the Object Manager to select it.
- In the Property Manager, click on the Plot tab.
- For a horizontal line, highlight the cos(X) text next to Y = F(X) = and type the desired value for the horizontal line. For instance, you might type 30, if you want the line displayed at Y=30.
- For a vertical line,
- Change the Type from Y=F(X) to X=F(Y).
- Highlight the cos(Y) next to the X = F(Y) = and type the desired value for the vertical line. For instance, you might type 400, if you want the line displayed at X=400.
- Highlight the value 12 next to Last value and type the axis maximum value. For a horizontal line, this should be the X maximum value. For a vertical line, this should be the Y maximum value.
- Highlight the zero next to First value and type the axis minimum value. For a horizontal line, this should be the X minimum value. For a vertical line, this should be the Y minimum value.
The line now extends the full length of the plot at the specified value. The line style and color can be changed on the Line tab in the Property Manager.
Axis Grid Lines:
Axis grid lines may be easier to use if you have many horizontal or vertical lines that you want to display. It may also be easier if the axis limits will change. To draw lines of constant value using the axis grid lines:
- Click on the existing worksheet or create a new worksheet.
- In one column, type each Y value for each horizontal line.
- In another column, type each X value for each vertical line.
- Save the data file.
- Click back on the plot window.
- For a horizontal line, click on the Y Axis to select it. For a vertical line, click on the X Axis to select it.
- In the Property Manager, click on the Grid Lines tab.
- Click the + next to the Worksheet Lines section.
- Check the box next to the Worksheet grid lines option.
- Change the None option next to Worksheet to the worksheet file that was saved in step 4.
- Change the Column to the desired column. For horizontal lines, this is the column created in step 2. For vertical lines, this is the column created in step 3.
The line now extends the full length of the parallel axis. The line style and color can be changed in the Worksheet line properties section.
Updated October 3, 2016