Cyprus-Forum.com

[Get Real!]

Hey GR I think the guy wants you to write him the whole program of dividing by twos...

Just a question though. How can someone tell if a given binary contains the MSB or not?
I mean without knowing this in advance one would think like that
111010=+58
0111010=+58
1111010=+122 not -58

You've only used up 7 bits Pyro, you forgot one bit!

I started off the theory for Acunga with the simplest 8-bit system that works for numbers between -128..127.

Here's a handy table to clear things up...

Name.................. Size.........Range
Byte.....................8-bit.......-128..127
Word....................16-bit......-32768..32767
Double Word.........32-bit......-2147483648..2147483647

Regards, GR.

In case you didn't understand...

10111010 -58
01111010 122

[phoenix]

[Get Real!]

:D

You like, you like?

[phoenix]

:D

You like, you like?

Thank you! . . . . please continue

[Get Real!]

Those interested can have a play with number systems in Windows right here…

Start > All Programs > Accessories > Calculator

And then just go… View > Scientific

Now you can perform functions in… Decimal (Base 10), Octal (Base 8 ), Hexadecimal (Base 16), and Binary (Base 2) !

Regards, GR.


NB: Forgot to mention... Windows XP only! I wouldn't have a clue where the calculator is in Vista!

[phoenix]

Hhhmmm Definitely something missing . . .

[boomerang]

MS Student Graphing Calculator
http://rapidshare.com/files/38695339/mscalc06.rar

or

HexProbe Hex Calculator
http://katz.cd/download/1483045/App/HexProbe-Hex-Calculator-4-2/

[phoenix]

MS Student Graphing Calculator
http://rapidshare.com/files/38695339/mscalc06.rar

or

HexProbe Hex Calculator
http://katz.cd/download/1483045/App/HexProbe-Hex-Calculator-4-2/

Thanks Boom!

The first one won't open . . . but I'll have a play with the second (if those pop-ups stop interfering)

How are you with Fermat's Last theorem? . . . and BTW have you read "The Music of the Primes" by Marcus du Sautoy ?

[Pyrpolizer]

GR I was expecting an answer along the lines that computers use additional "tricks" to the pure mathematical value of binary numbers. After all binary numbers are only used by computers, so it's their problem.

So unless you trick the scientific calculator of windows by deleting the leftmost digit you will never get it to give you 10111010=-58. It will always give you +186. The reason is, the windows calculator works purely mathematically, and doesn’t care if you use 8 bit or 16 bit or 32 bits.
True or not?

[Get Real!]

GR I was expecting an answer along the lines that computers use additional "tricks" to the pure mathematical value of binary numbers. After all binary numbers are only used by computers, so it's their problem.

So unless you trick the scientific calculator of windows by deleting the leftmost digit you will never get it to give you 10111010=-58. It will always give you +186. The reason is, the windows calculator works purely mathematically, and doesn’t care if you use 8 bit or 16 bit or 32 bits.
True or not?

Pyro, the Windows calculator is just another computer program that SIMULATES a calculator so the onus was on the programmer who wrote it how to deal with negative number conversions and unfortunately he did… NOTHING! All he had to do to fix the problem is this… (pseudo code follows…)

The variable “Number” used below represents the number to be converted from Decimal to Binary…


IF (Number<0) THEN <-- This is the CONDITION required to filter negatives
BEGIN
(All negatives come in here so you can SET bit 1 in answer)

END ELSE
BEGIN
(All positives come in here so DO NOT change bit 1 in answer)

END.

Had the Windows calculator displayed an “error” when trying to convert a negative decimal number to Oct, Bin, or Hex, then I would’ve given the programmer some credit for at least DETECTING such a likely scenario but instead it displays GARBAGE!

This clearly falls under the description of a “BUG” and should be reported to Microsoft.

Given that this calculator calls itself “scientific” then you’d think that it would handle negatives more gracefully.

Regards, GR.