Apple IIe - Page 154

154 Apple lie Users Handbook
10 GR
20 COLOR= 2
30 PLOT 20,10
40 COLOR =6
50 PLOT 30 , 35
Example
60 PRINT SCRN(20,10), SCRN(30,35), SCRN(10,0)
70 END
In
the preceding example, line 10 initializes the low resolution
screen. Lines 20 to 50 plot two different colored dots on the
screen. Line 60 displays the color value of the corresponding
dots. Notice that the value of SCRN(10,0) is zero. There is a black
dot at that position.
•
Applesoft
SGN • Integer
The SGN function returns a +1 if its argument is positive, a -1 if
negative, and a 0 if zero .
Configuration
SGN (a)
Example
100 A= 100
200 X = SGN(A)
300 PRINT X
400 END
]RUN [Ret]
1