How to Graph Complex Functions With Excel

By Amy Dombrower

Microsoft Excel manages complex data, which you can then plot to display a graph of a function. Before setting up a chart, you need to enter the function's x and y data. In order to make Excel calculate the function of y in terms of x, you first need to enter some values of x, which will make up the parameters of the graph. Use the scatter plot to graph a complex function, which is the only Excel chart type that graphs two sets of value data (x and y) against each other (as opposed to categorical data on the x-axis).

Things You'll Need

  • Microsoft Excel

Step 1

Open a blank workbook in Microsoft Excel.

Step 2

Enter "x" in cell A1. Press "Tab" to go to the next column over. Enter "y" in cell B1.

Step 3

Select cell A2. Enter the first value of x you want to use for the horizontal axis. For instance, to span the negative and positive axes, enter "-5," and in each cell below, enter the next value in the series, up to 5. Enter "-4" in cell A3 and onward...-3, -2, -1, 0, 1, 2, 3, 4, 5.

Step 4

Select all the x values in column A by highlighting A2 and dragging your cursor down to the last cell. You need to define the name of the values, so Excel knows that each value in column A equals a value of x. This will be used when you create a formula in the y column. Click the "Formulas" tab. In the "Defined Names" group, click "Define Name." Enter "x" in the "Name" box. Click "OK."

Step 5

Select cell B2. Enter a complex function that you want to graph. If you are graphing a linear equation with the format y=mx + b, enter "=m*x + B" in cell B2. Tab over, and Excel will calculate the formula with the corresponding value of x.

Step 6

Copy the formula from cell B2 to the other cells. Select cell B2. Click the "Home" tab. Click "Copy" in the "Clipboard" group. Click and drag over the cells below B2 to select them. Click the arrow underneath the "Paste" icon in the "Clipboard"group. Choose "Formulas." The formula is added to each cell in the B column and contains each y-value in terms of x.

Step 7

Highlight all the cells. Click the "Insert" tab to create a graph for the function.

Step 8

Click "Scatter" in the "Charts" group. Choose a subtype for the scatter chart. The chart immediately is displayed on your worksheet.

Step 9

Click the chart to select it. The "Chart Tools" appear on the Ribbon, which include the "Design, Layout and Format" tabs. Browse through these tabs to make changes to the chart style, chart layout and the layout of individual chart elements, such as chart title, axes, legend and data labels.

Step 10

Click a chart element directly on the worksheet to edit any titles you want to change.

Step 11

Click the "Microsoft Office Button," and select "Save as" to save the graph and data.