Greatest Integer Function

The greatest integer function, denoted by int, is defined as follows:

int(x) = greatest integer less than or equal to x

The greatest integer function is found in the catalog.

To obtain a graph of the greatest integer function, press Y= to access the equation editor. Enter Y1 = int(x) as follows:

press CATALOG (located above the 0 key) press I (located above the key) select int( press press press ) press

The function Y1=int(X) is entered into the Y= editor. We are now ready to view a graph of the greatest integer function. Press to access the zoom menu. Press to select 6:ZStandard. One then obtains the graph shown at the right. In this graph, the steps of the int function are inappropriately connected.

To obtain a correct graph, we must change from the line to the dot style. Press Y= to return to the equation editor. Highlight Y1=int(X). With int(X) highlighted, press the left thumb pad arrow twice so that the slanted line to the left of Y1 is blinking. Press six times (the blinking icon changes to three dots indicating the dot style). Press . The steps in the graph of the greatest integer function are now disconnected.

For a better view, press to access the zoom menu, then press to select 5:ZSquare. From the zoom square presentation, press to access the zoom menu again, then press to select 2:Zoom In. Press in response to X = 0 and Y = 0 to zoom in from the origin. Then press to clear the extraneous information from the graph. If needed, reset the WINDOW with xscl = 1 and yscl = 1 to obtain the graph displayed at the right. Note that the step from is occluded by the x-axis.