The Graph Tools | Plot Tools | Calculate Area command computes the area under a line/scatter plot, ribbon/wall plot, or 3D XYZ line/scatter plot. When calculating area for 3D XYZ line/scatter plots, the area is calculated only for the XY plane. The area is reported in the graph's XY units using zero as the base line.
To calculate the area:
- Create a line/scatter, ribbon/wall, or 3D XYZ line/scatter plot using the Home | New Graph | Basic commands.
- Click on the plot to select it.
- Click the Graph Tools | Plot Tools | Calculate Area command.
- Enter a baseline value (Y value to calculate the area down to, default is zero) into the Area Baseline Value dialog and click OK.
- A Grapher - Report window opens containing the area and information such as the data file, X column, and Y column used to create the plot. The area is reported in the graph's XY units.
Area Tip 1
The area is calculated by finding the area between the plot and baseline value entered in the Area Baseline Value dialog. If any part of the plot extends below the baseline value, a negative area is calculated and this value is added to the total area. The area report displays area Above Baseline Area, Below Baseline Area, and Total Area.
Area Tip 2
The units for the area are X units * Y units. For most situations, the X and Y values should be in the same units before using this command for the calculated area value to make sense.
Updated December 11, 2017