How do I determine the binary code (0's and 1's) of a number? ------------------ I wish there was a button on my monitor to turn up the intellegince. Theres a button called 'brightness' but it doesn't work

"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning."

and if that doesnt confuse you, for a "twos complement" negative number, take the positive binary number, reverse all the 0's and 1's then add 1. 1 = 0001 -1 = 1110+1 = 1111

I meant without using java code. ------------------ I wish there was a button on my monitor to turn up the intellegince. Theres a button called 'brightness' but it doesn't work

Start with dividing the number by two. 14/2 = 0, and the dividend(I am pretty certain this is the wrong word) is 7. Divide 7 by 2 again. The remainder is 1 and the dividend is 3. Divide 3 by 2. Remainder is 1 and dividend is 1. Since 1<2, we stop the division here. Now, write the remainders from right to left. In this case, the binary value of 14 would be:1110. You can apply this process to any number, to get its binary equivalent. But, as Grant has suggested, calculators are always a good bet.

Brett Knapik
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Ok, great thanks, anymore tips are welcome ------------------ I wish there was a button on my monitor to turn up the intellegince. Theres a button called 'brightness' but it doesn't work

Brett Knapik
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hmm... I think I missed something here. I am trying 86 so 86/2=43 43/2=21 r1 21/2=10.5 ?? 10.5/2=5.25 ?? 5.25/2=2.625 ?? 2.625/2=1.3125 ?? would the answer be 011111? I doubt it there must have been some rules left out or a misunderstanding. ------------------ I wish there was a button on my monitor to turn up the intellegince. Theres a button called 'brightness' but it doesn't work [This message has been edited by Brett Knapik (edited February 06, 2001).]

Here's how I do it. I write out the decimal values corresponding to each binary digit: 128 64 32 16 8 4 2 1 Then I take my number, and find the biggest one that would fit, in the example, it was 86, so ti put a 1 under 64: 128 64 32 16 8 4 2 1 0 1 Then subtract 64 from 86, leaving 22, take 22, and put a 1 under 16: 128 64 32 16 8 4 2 1 0 1 0 1 Leaving 6, repeat the process, and you get: 128 64 32 16 8 4 2 1 0 1 0 1 0 1 1 0 And that's the binary for 86. You can double-check your answer, by adding 64 + 16 + 4 + 2 = 86 There are probably faster ways of doing it, but I think this is the easiest. Well, I can't get the numbers to line up right, but I think you get the idea. [This message has been edited by Matthew Jones (edited February 06, 2001).]

Brett Knapik
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according to my test program the answer should be 1010110 here is the source code. I used Tony's way of getting the answer. One of the ways are wrong, which one could it be?

------------------ I wish there was a button on my monitor to turn up the intellegince. Theres a button called 'brightness' but it doesn't work [This message has been edited by Brett Knapik (edited February 06, 2001).]

Brett, You are almost there, just a little more formaility. What you want to is iterate through every power of 2 from the largest power that fits down to 1 (2 to the 0 power). So for 86 (the largest power of two is 6 or 64) does 64 fit into 86 (yes) so you have a 1 {now subtract 64 from 86} does 32 fit into 22 (no 32 > 22 ) so you have a 0 does 16 fit into 22 (yes) you have a 1 (subtract 16 from 22) does 8 fit into 6 (no) you have a 0 does 4 fit into 6 (yes) you have a 1 (subtract 4 from 6 ) does 2 fit into 2 (yes) you have a 1 (subtract 2 from 2) does 1 fit into 0 (no) you have a 0 were done with 2 to the 0 so we are done (now concatinate the 0's and 1's 1010110 or 64 + 16 + 4 + 2 = 86

Brett Knapik
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ok so i'll try the number 72. 72-64 = 8 8-8 = 0 so the answer would be 1001000. ok just one more quick question is there a trick for figuring out negetives and what is this sign bit thing, how can i distinguish that. ------------------ I wish there was a button on my monitor to turn up the intellegince. Theres a button called 'brightness' but it doesn't work

Brett, Start with 86... NOTE R stands for remainder. 1. 86 / 2 = 43 R = 86 % 2 = 0 2. 43 / 2 = 21 R = 42 % 2 = 1 3. 21 / 2 = 10 R = 21 % 2 = 1 4. 10 / 2 = 5 R = 10 % 2 = 0 5. 5 / 2 = 2 R = 5 % 2 = 1 6. 2 / 2 = 1 R = 2 % 2 = 0 7. 1 / 2 = 0 R = 1 % 2 = 1 Writing this answer from #7 to #1 from you get: 1010110. With 72, you do the same thing. 1. 72 / 2 = 36 R = 72 % 2 = 0 2. 36 / 2 = 18 R = 36 % 2 = 0 3. 18 / 2 = 9 R = 18 % 2 = 0 4. 9 / 2 = 4 R = 9 % 2 = 1 5. 4 / 2 = 2 R = 4 % 2 = 0 6. 2 / 2 = 1 R = 2 % 2 = 0 7. 1 / 2 = 0 R = 1 % 2 = 1 Answer from #7 to #1 is: 1001000. -Peter

Brett Knapik
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I find steve's way easier and the answer matches yours peter ------------------ I wish there was a button on my monitor to turn up the intellegince. Theres a button called 'brightness' but it doesn't work

Peter has given the text book method which is 100% correct, we can do it other way also manually if the number is small enough.

Peter Tran
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Brett, To the other part of your question, if you want the negative of a number then get the binary value of the positive value. Negate all bits and add 1. NOTE, carry out any leading 0 to your sign bit. Assuming a byte (8 bits) below. E.g. From above example, 86 is 01010110. Note my sign bit (position #8 is 0 for positive sign). 1. Get binary result for positive value. 86 -> 01010110. 1. Negate all bits: 10101001. 2. Add 1 -> 10101010 = -86. Note, since I'm assuming a byte which has 8 bits, my sign bit (bit #8) is now 1. -Peter