Enter Data for a Scatter Plot in the Graphs Application
You can use the Lists & Spreadsheet application on the TI-Nspire to enter data to construct a scatter plot. Before you perform a regression, it’s almost imperative that you view a scatter plot of the data to assist you in deciding on an appropriate model. An inspection of a scatter plot can reveal this information efficiently.
Here are the steps to enter the data in a Lists & Spreadsheet page:
To start with a new document, press [CTRL][N] (a shortcut key sequence) or press [ON]→New Document.
If you currently have an open document, you are prompted to save the document. Press [ENTER] for Yes or press [TAB][ENTER] for No.
On the next screen, select Add Lists & Spreadsheet and press [ENTER].
Before entering your data, it’s a good idea to name your lists.
It’s always a good idea to choose names that convey the meaning of the data the lists represent because the list names show up as the x– and y-variables of the scatter plot.
Use the Touchpad to move your cursor to the column list name area.
Type your list name using the alpha keys and press [TAB] to move to the column list name area in column B.
Again, type a name that describes the data, and then move to column C and choose a meaningful name for that data.
Enter the data in column A.
Notice that the data for year forms the arithmetic sequence 0, 10, 20, . . . , 100. Here are three time-saving options for entering this data that eliminate the need to actually type each number:
Use the Fill command with a formula. Type the number 0 in cell A1. Next, type the command =a1+10 in cell A2 and press [ENTER]. Position the cursor back in cell A2 and press [MENU]→Data→Fill. Notice that the box around cell A2 becomes dashed, indicating that it has been selected. Press the
key repeatedly until the dashed box reaches row 11 and press [ENTER]. The third screen shows that the sequence is complete.
Use the Fill command without a formula. Type 0 in cell A1 and 10 in cell A2. Next, position the cursor in cell A1, press the [SHIFT] key, and press
once to highlight cells A1 and A2, as shown in the first screen. Press [CTRL][MENU]→Fill. Then press the
key repeatedly until the dashed box reaches row 11, and press [ENTER]. The second screen shows that the sequence is complete.
This method of highlighting two cells to generate a sequence works only for a sequence that is arithmetic, meaning that each term is generated by adding or subtracting the same value from the previous term. If you want to create a different sequence, such as the geometric sequence 1, 2, 4, 8, . . . , 128, use Fill with a formula or the method shown in the next bullet.
Use the Sequence command. Position the cursor in the column A formula cell (the gray box located above row 1) and press
Press [S] to quickly jump to the commands that begin with the letter S, and then locate the sequence command using the Touchpad keys. Use the syntax example at the bottom of the Catalog page to help you enter the sequence correctly. Here, a recursive sequence is configured by typing =seq(10(n-1),n,1,11). Press [ENTER] to execute the command and populate cells A1 through A11 with the values 0, 10, 20, . . . , 100.
Enter the data for columns B and C.
The data for column B and that of column C must be entered manually.