HP 48G - Page 14

PLOT
lets you draw some 15 types of mathematical
plots, including simultaneous and 3-D plots.
Example: Plot tan x. Press (2]PLOT), highlight TYPE:
and press [4,]!]!] to see your choices.
1. Highlight Furnct ion and press IFTEEL
2. Set radians mode (highlight :; or (+/9).
3. Reset default parameters (center on the origin,
use coordinate axes, and put an axis mark every
10 pixels, representing 1 unit): Press (NxT) 33,
select Fe=et pliot and press INTEN.
4. Next, highlight Ez: and type (")(TAN] @] X)ENTER).
Now, you can leave the default viewing scale or
-AUTOZCALE (which samples x-values to
estimate a y-range), or enter specific vertical and
horizontal ranges. For now, leave the defaults.
5. Press I3 (to clear prior plot), and [TTIRE.
After a first plot, you'll want to adjust it at the
screen (press to see the main PLOT screen).
At PLOT OPTIOME, you set the calculation (not the
view) range for the independent variable (the default
isthe view range). You can also set connectedmode:
If _.COMMELTED is unchecked, only 1 pixel per column
is lit on the plot; if -COMMELTED is checked, additional
pixels are litto give the graph a continuous look.* (Try
repeating the above with _COMMECTEDL unchecked.)
Interactive Graphing Features
Once you've drawn a plot, the arrow keys move a set
of crosshairs.** toggles the crosshairs to “invert”
(white-on-black) if needed. Press or(+ and
crosshair coordinates appear below (press any menu
key to return the menu labels). Use to put the
crosshairs on the graph. Press again for co-
ordinates of a point on the graph.
Look more at the interactive menu: The fii[gll folder
offers tools for rescaling your view. H:thf4 lets you
draw a box to show a desired viewing window;
*In the example, it only appears that “vertical asymptotes” have been
drawn; the plotter has just connected the pixels across the asymptotes.
Note, however, that if such a discontinuity falls exactlyon the coordinate
of a column of pixels, the graph won’t connect over the discontinuity.
**[ENTER) puts the crosshairs coordinates on the stack, but note: those
are pixel coordinates—not necessarily a point on your function graph.
12 THE HP 48G/GX Pocker GuIiDE