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<DIV><FONT size=2><FONT color=#000080><FONT face=Courier>There's a typo in the
version of the Compton refraction app to which this msg is attached. Rather than
repost the entire app, I'll just post the CORRECTION here. It's commented out,
but if you want to use it's program-flow switching, cut-&-paste it into the
program, being sure to replace the correlated line in the
program.</FONT></FONT></FONT><FONT face=Courier><FONT
color=#000080></FONT></FONT></DIV>
<DIV><FONT size=2><FONT color=#000080><FONT
face=Courier></FONT></FONT></FONT><FONT face=Courier><FONT
color=#000080></FONT></FONT> </DIV>
<DIV><FONT color=#800000 face=Courier size=2>'scatter% =
'uncomment to turn off the 'scattering' step</FONT><FONT face=Courier><FONT
color=#000080></FONT></FONT></DIV>
<DIV><FONT size=2><FONT color=#000080><FONT
face=Courier></FONT></FONT></FONT><FONT face=Courier><FONT
color=#000080></FONT></FONT> </DIV>
<DIV><FONT size=2><FONT color=#000080><FONT face=Courier>should
be:</FONT></FONT></FONT><FONT face=Courier><FONT
color=#000080></FONT></FONT></DIV>
<DIV><FONT size=2><FONT color=#000080><FONT
face=Courier></FONT></FONT></FONT><FONT face=Courier><FONT
color=#000080></FONT></FONT> </DIV>
<DIV><FONT color=#000000 size=2><FONT color=#ff0000
face=Courier><STRONG>'scatter% = 0 'uncomment to turn off the
'scattering' step</STRONG></FONT></FONT></DIV>
<DIV><FONT color=#000000 size=2><FONT color=#ff0000
face=Courier><STRONG></STRONG></FONT></FONT> </DIV>
<DIV><FONT color=#000080 face=Courier size=2></FONT><FONT color=#000080
face=Courier size=2>The line occurs shortly after the preliminary-comments
section of the app's code.</FONT></DIV>
<DIV><FONT color=#000080 face=Courier size=2></FONT> </DIV>
<DIV><FONT color=#000080 face=Courier size=2>Sorry about the inconvenience. I
must've inadvertantly deleted the "0" [the "switch" value]
while preparing the final 'state' of the app for posting.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT color=#000080 face=Courier size=2>BTW, the posts containing program
code are meant to be saved in their entirety.</FONT></DIV>
<DIV><FONT color=#000080 face=Courier size=2></FONT> </DIV>
<DIV><FONT color=#000080 face=Courier size=2>Thus "save"-d, hey can be
"open"-ed in the QBasic interpreter just as they were
posted.</FONT></DIV>
<DIV><FONT color=#000080 face=Courier size=2></FONT> </DIV>
<DIV><FONT color=#000080 face=Courier size=2>That's why the preliminary comments
have leading [']s.</FONT></DIV>
<DIV><FONT color=#000080 face=Courier size=2></FONT> </DIV>
<DIV>
<DIV><FONT color=#000080 face=Courier size=2>Aside: The QBasic interpreter ships
with Windows, although most installations skip it. [In some versions of Windows,
it was [apparently to me] left out. If that's the case, just keep looking back
through your Windows installation 'disks' [CD ROMs], beginning with the newest
set, until you find it. Most likely, the version you find will work. There's no
"installation" just copy the files to your hard drive. [You might have
to decompress them using the utility for doing so that's usually in the
"Windows" directory. "uncompress.exe", or comething like
that.] It's a simple programming language, but one can do serious stuff with it
because one can drive computers by writing instructions in QBasic. The QBasic
language can be explored via the adequate "Help" system that ships
with the interpreter. Be sure to install this too, so you can use it as a
reference. [Having QBASIC on a computer to which your Children have access is an
especially-good way of introducing them to what they can actually do with
computers, besides 'play games'. If you can afford it, though, and you've this
interest on behalf of your Children, I suggest you get them started by
purchasing a modern compiler language, like C++, Visual Basic, or one of
the Borland compilers. [If you trun them lose into programming, however, you
should give them a separate Login ID to a Protected Operating system - or, if
you can afford it, a separate machine, especially if they're going to be
programming in a powerful language like C++ - so they don't inadvertantly
'trash' the machine on which you do your 'balance your checkbook'
stuff.</FONT></DIV>
<DIV><FONT color=#000080 face=Courier size=2></FONT> </DIV>
<DIV><FONT color=#000080 face=Courier size=2>I prefer to use a modern 'visual'
programming language. But those languages either produce machine language
executable code, or the compiler must be purchased to execute the source
code.</FONT></DIV>
<DIV><FONT color=#000080 face=Courier size=2></FONT> </DIV>
<DIV><FONT color=#000080 face=Courier size=2>So, when I've a 'point' to make
that needs generalized access, I write a QBasis program, and make the source
code available. QBasic is an interpreted language. It 'interprets' the source
code line by line as the program executes, so there can be no 'funny-business'
hidden from the user. [There is a "Quick Basic Compiler" which allows
the source code to be translated into stand-alone machine code
[".exe"]. I own it, but don't use it for these little apps because I
want folks to be able to study, and learn from, the source code.]</FONT></DIV>
<DIV><FONT color=#000080 face=Courier size=2></FONT> </DIV>
<DIV><FONT size=2><FONT color=#000080><FONT face=Courier>QBasic has an
incomplete, but sufficient, implementation of Trig functions. Any problem can be
resolved via Trig, so QBasic is sufficient.</FONT></FONT></FONT><FONT
face=Courier><FONT color=#000080></FONT></FONT></DIV></DIV>
<DIV><FONT face="" size=2><FONT color=#000080><FONT
face=Courier></FONT></FONT></FONT><FONT face=Courier><FONT
color=#000080></FONT></FONT> </DIV>
<DIV><FONT face="" size=2><FONT color=#000080><FONT face=Courier>Cheers,
Y'all,</FONT></FONT></FONT><FONT face=Courier><FONT
color=#000080></FONT></FONT></DIV>
<DIV><FONT face="" size=2><FONT color=#000080><FONT
face=Courier></FONT></FONT></FONT><FONT face=Courier><FONT
color=#000080></FONT></FONT> </DIV>
<DIV><FONT color=#000080 face=Courier size=2>K. P.
Collins</FONT></DIV></BODY></HTML>
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