Calculating the area under a curve:

1. Create a line/scatter, ribbon/wall, or 3D XYZ line/scatter plot using the Home | New Graph | Basic commands.
2. Click on the plot to select it.
3. Click the Graph Tools | Plot Tools | Calculate Area command.
   
4. Enter a baseline value (Y value to calculate the area down to, default is zero) into the Area Baseline Value dialog and click OK.
5. 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.

Tips for calculating area: 

• Grapher calculates 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 will be calculated. This negative value will then be added to the total area.
  
  
• The area report displays calculations for: Above Baseline Area, Below Baseline Area, and Total Area.
  
  
• 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 May 2023