Franklin Bretschneider, a user and beta tester of TapBASIC presents two useful TapBASIC programs.
Sine Waves
Graph some sine waves.
rem graphing waveform*
clrmem
dim x(33)
dim y(33)
for a = 1 to 33
x(a) = (a-1)/10
y(a) = 1.5+sin(2*x(a))+0.33*sin(6*x(a))
next
for a = 2 to 33
line 3+60*x(a-1),60*y(a-1),3+60*x(a),60*y(a),r
next
text "finished - open graph screen"
Click to Download
Camera exposure calculator
This program is an electronic simulation of “Focus Columbus”, the venerable old 1950′s exposure calculator, which consisted of two pivoting aluminium disks with numbers for film sensitivity, diaphragms and exposure times, how they depend on date, time of day, weather and scene type.
Although modern cameras have automatic exposure, it still very useful, because one can, at home, and late at night, predict what one will need the next day out, for example camping in the woods.
clrmem
text "Focus Columbus"
text " compute exposure"
ask " film speed in ISO=",a
s= log(800/a)/log(2)
ask " Month (1 .. 12)",m
n=int(abs(m-6)/1.6)
ask "hour=",h
if m<3
h=h+1
endif
if m>=10
h=h+1
endif
g=int(abs(h-12)/1.1)
t=n+g
input "Weather (1 light ... 4 dark)",w
text " "
text "Subject ( 1 landscape, 2 street,"
text "3 forest, 4 room)"
input "choose 1 ... 4",x
input "property 1 light ... 4 dark",l
y=24-(s+t+w+3*(x-1)+l)
text"EV="+y
text "Aperture .... time"
for i = 0 to 5
a = 2^i
t = (2^y)/(a^2)
text"A="+a+" t=1/"+t
next
Click to Download
Feel free to submit your own programs in the comments!
