# HP Forums

Full Version: Casio Prizm screenshot
You're currently viewing a stripped down version of our content. View the full version with proper formatting.

Here is a screenshot from the Casio Prizm, showing the graph of two inequalities, y>=x+1 and y<2x+3. The dark shaded area is the solution to both inequalities. The actual screen looks somewhat crisper than the screenshot.

What an improvement compared to what we can do with an HP-48G:

Since I'm not that familiar with plotting I had to consult the manual. You need two different plot-types: TRUTH and CONS.
As suggested in the manual I created two variables:

INEQ

'Y\>=X+1 AND Y<2*X+3'


EQNS

{ 'Y=X+1' 'Y=2*X+3' }


Now you can choose one or the other for EQ. Don't ERASE the graph after drawing the first plot.

Currently I'm reading the fun of programming.
There's a chapter dealing with images (7 Functional images). So I wondered whether I could do that with my HP-48 as well. Here we go:

## Checker

checker

\<<
FLOOR SWAP
FLOOR +
2 MOD
NOT
\>>


EQ

\<< Y X checker \>>


## Polar Checker

toPolar

\<<
R\->C DUP
ABS SWAP ARG
\>>


n = 10

EQ

\<<
Y X
toPolar
\pi /
n *
checker
\>>


## Swirl Vertical Strip

vstrip

\<< ABS .5 \<= \>>


fromPolar

\<<
\-> r \Gh
\<<
\Gh SIN r *
\Gh COS r *
\>>
\>>


r = 1

EQ

\<<
Y X toPolar
OVER
2 * \pi *
r / +
fromPolar
vstrip
\>>


Now this turns out to be very slow. Moreover I received an "Insufficent Memory" error and had to plot the image in several runs. Not exactly what you want.

Still I hope these examples might be inspiring.

Best regards

Thomas