Talk:False position method

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[edit] Removal dd 4 Febraury 2005

I removed the text because I found it impossible to justify. Calculus is not needed to arrive at the idea of secant lines. The linear problems mentioned in the Nine Chapters do not use secant lines; in fact, I would argue they do not use the false position method either but linear interpolation. Finally, I could not find any evidence in History of calculus and Moscow and Rhind Mathematical Papyri that the Egyptians developed calculus, except for the false statement that one needs calculus to calculate the volume of a frustum. -- Jitse Niesen 18:18, 4 Feb 2005 (UTC)

[edit] Egyptian mathematics

To the editor with IP address 209.150.67.45: Could you please explain (or give references explaining) how the ancient Egyptians used the false position method? The example in Egyptian mathematics suggests that given an equation ax = b, they try one value, say y, compute ay and compare the result with b to get the solution. I am trying to understand the differences with the method of double false position as used by the Chinese. Thanks, Jitse Niesen 10:24, 4 Apr 2005 (UTC)

[edit] Rule of False Position?

How does the method described in this article fit in with the "method of false position" described at [1] and [2]? Do we need to say something here about other uses of the terminology? Tom Harrison Talk 20:53, 6 May 2006 (UTC)

Yes, it should be mentioned, perhaps via a disambiguation page. I think that the methods are related, but the rule of false position described on the web pages you mention is considerably less sophisticated. I haven't found a good reference on this though. -- Jitse Niesen (talk) 12:15, 7 May 2006 (UTC)
Another external link for when the Rule of False Position page is created: *Rule of False Position at Convergence --Nic bor 18:23, 3 July 2007 (UTC)

[edit] different visualisation

Visualisation of the false position method.
Visualisation of the false position method.

is anyone interested in integrating this into the article? i find it looks a bit nicer than the old one... —The preceding unsigned comment was added by 212.117.72.126 (talk • contribs) 17:06, 31 May 2006 (UTC)

212.117.72.126: It is "do it yourself" around here. Why not add it yourself, if you think that it is good. But I would not remove the old diagram, if I were you. JRSpriggs 04:52, 1 June 2006 (UTC) P.S. You should give copyright information (who created it and confirmation that he/she gave permission) even for diagrams posted on talk pages like this one.

[edit] Division vs. multiplication

Regarding the example code: since the compiler will convert the floating-point division by a constant into a floating-point multiplication by the (precomputed) reciprocal of that constant at compile time, there is no need to make the code less clear in order to gain speed: the machine code generated will be the same in either case. -- The Anome 12:05, 11 January 2007 (UTC)

Even faster than multiplying by one half, is shifting one bit to the right. Which optimization the compiler will also do for us, if it is any good (and knows what the constant is). More important still is that the code should be clear to the reader. JRSpriggs 05:35, 12 January 2007 (UTC)