Graphing

For raw data that should fall on a straight line, one normally plots the raw data with markers and then draws the best line through those points. Below are some guidelines to getting started. The help menu has a big section of graphing.

 
• Enter the x- and y-values in adjacent columns.
• In a third column, type =linfit(x-range,y-range) into the cell at the top of the set of rows containing the x- and y-values. The arguments x-range and y-range can be inserted by selecting the rows which contain the x-values and y-values, respectively. The linfit function fills all cells below the cell where it is entered with points that fall on a straight line.
• Highlight all rows for the three columns that contain data. From the Menu bar, select Graph | New | Scatter
• Two graphs should appear. What combination of markers and lines appear will depend on the default set up. Assuming the defaults are not properly set, choose Edit | Data Sets from the graph menu bar.
• A new dialog box appears. In the upper left, a slide bar indicates the Data Set and should say set 1 initially. From this dialog box you can change the range of x and y values and choose the character with which data are plotted and/or connected. For data set 1, the Line Style should say "no line" and the Marker should say "Square". Slide the data select bar to Data Set 2. The Line Style should say "Solid" and the Marker should say "None".
• Under Options there are several choices; Choose General for a graph title, X-axis for labeling the x-axis and Y-axis for labeling the y-axis.
• Under the File menu, save the graph with a meaningful name.
• The graph may be and usually should be transferred to the spreadsheet. Click on a empty cell with room to the left and below to paste the graph into the spreadsheet. Choose Graph | Insert in Sheet to paste the graph into the spreadsheet.