php precision math

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Benjamin
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Post by Benjamin »

I believe Roja knows what he is talking about. Lets not argue like children now.
Last edited by Benjamin on Mon Jun 19, 2006 1:07 pm, edited 1 time in total.
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Oren
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Post by Oren »

We are not arguing here, this is just curiosity.
Roja
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Post by Roja »

Oren wrote:We are not arguing here, this is just curiosity.
I find it to be arguing.

However, lets put it to rest soundly.

The word for the bar on top of the numbers is called a "Vinculum", and it is an accepted math form worldwide for expressing repeated numbers.

http://www.pballew.net/arithme6.html#vinculum

It is used worldwide, in widely acclaimed books, and is the encouraged symbol to use in MathML (as an "overbar") for expressing repeated numbers. MathML is the international standard for math expressions.

Better, it is also what Mathematica ("The most widely used math program in the world") uses and suggests.

I'm really not sure how much more I could defend such a silly argument, but if you feel the need to continue, start another thread because it has absolutely NOTHING to do with whether accepting unfiltered posts is insecure.

Enough with the thread hijacking. If you have curiosities about floating point accuracy, and math terms, open a new thread!
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John Cartwright
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Post by John Cartwright »

carry on, topic split.
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Oren
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Post by Oren »

Yeah it was a little bit of topic and I was actually going to say that myself.
Anyway... let's don't argue. I agree that it sounded a little bit like arguing, but that wasn't my intent. What can I say? I'm a curious guy :wink:
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feyd
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Post by feyd »

slightly off topic, but a 3-4-5 is a Pythagorean triangle.
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Oren
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Post by Oren »

feyd wrote:slightly off topic, but a 3-4-5 is a Pythagorean triangle.
You are almost there feyd :P You gave the general name... What I mean is that 5-12-13 is also a Pythagorean Triangle for example and so 8-15-17. So I can't say you are wrong, but it's not what I meant. 3-4-5 is called: Egyptian Triangle :wink:
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feyd
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Post by feyd »

I'm exactly there. You didn't specify a specific, unique name.
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Christopher
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Post by Christopher »

It is interesting, but not that suprising, that there are different names and conventions around the world. At least two have been mentioned here:

- The first is that 0.3 is shorthand for 1/3 some places, other places it is just 0.3 and 1/3 is 0.3333 or some other notation. I'm from the US so have never heard the former.

- The second is the use of the terms Pythagorean triangle and Egyptian Triangle. I know Pythagoras's theorem (a² + b² = c²). And I know the Egyptians and others found right triangles whose sides are whole numbers early on. But I've never heard of either term.
(#10850)
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Maugrim_The_Reaper
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Post by Maugrim_The_Reaper »

Here, its usually the triple dot (...), or a bar over the numbers.
3 Years of statistical analysis, and it's always been an "overbar" when it crops up... Sorry for not pointing out the human shorthand is not used in binary land which I was sort of hinting :).
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