Re: [Edu-sig] Brute force solutions

2005-09-24 Thread [EMAIL PROTECTED]
The fun part here is we can use numerator/denominator syntax with open-ended precision integers, to like express sqrt of 19 as some humongous fraction (as many digits as memory will allow). This lets us far surpass the floating point barrier. For example, the sqrt of 19 is rougly:

Re: [Edu-sig] Brute force solutions

2005-09-24 Thread [EMAIL PROTECTED]
n = ((pow(orig,0.5) + addterm)/denom)**2 H, this may be the Achilles heal of my project, to not use any sqrt finder in the process of finding a sqrt using continued fractions. Back to the drawing board? Kirby

Re: [Edu-sig] Brute force solutions

2005-09-24 Thread Scott David Daniels
[EMAIL PROTECTED] wrote: The fun part here is we can use numerator/denominator syntax with open-ended precision integers, to like express sqrt of 19 as some humongous fraction (as many digits as memory will allow). This lets us far surpass the floating point barrier. OK, here we go: def

Re: [Edu-sig] Brute force solutions

2005-09-22 Thread John Zelle
On Wed, Sep 21, 2005 at 09:31:41AM -0700, Kirby Urner wrote: Of course all of this requires temporarily ignoring the fact that algebraic methods give us a way to compute phi as simply (1 + math.sqrt(5))/2.0. I've been considering this a bit. The closed form here begs the question, what is

Re: [Edu-sig] Brute force solutions

2005-09-22 Thread Daniel Ajoy
On 22 Sep 2005 at 12:00, (Kirby Urner) wrote: Some lessons that might be learned from this approach: (1) when working with floats, you want to compare differences, not check for equalities, e.g. looking for when b/a == 1/b would be a bad idea. (2) you get greater accuracy in

Re: [Edu-sig] Brute force solutions

2005-09-22 Thread Arthur
-Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Daniel Ajoy Sent: Thursday, September 22, 2005 10:07 AM To: edu-sig@python.org Subject: Re: [Edu-sig] Brute force solutions My approach to teaching about phi is by asking kids to draw construction

Re: [Edu-sig] Brute force solutions

2005-09-22 Thread Kirby Urner
I've been considering this a bit. The closed form here begs the question, what is math.sqrt(5)? Sure, we have a built-in function that computes this, but someone had to write the algorithm that computes sqrt. That calculation makes use of numerical techniques similar to what we are discussing

Re: [Edu-sig] Brute force solutions

2005-09-21 Thread David Handy
I'm sorry, but I couldn't help taking Kirby's findphi() function as a personal challenge. At the cost of roughly doubling the complexity of the code (19 lines instead of ten lines in the function body), I was able to improve the performance by a factor of more than 6500, while basically still

Re: [Edu-sig] Brute force solutions

2005-09-21 Thread Peter Bowyer
At 14:33 21/09/2005, you wrote: At the cost of roughly doubling the complexity of the code (19 lines instead of ten lines in the function body), I was able to improve the performance by a factor of more than 6500, while basically still using the same brute-force approach of guessing a number,

Re: [Edu-sig] Brute force solutions

2005-09-21 Thread David Handy
On Wed, Sep 21, 2005 at 06:44:01PM +0100, Peter Bowyer wrote: At 14:33 21/09/2005, you wrote: At the cost of roughly doubling the complexity of the code (19 lines instead of ten lines in the function body), I was able to improve the performance by a factor of more than 6500, while basically

Re: [Edu-sig] Brute force solutions

2005-09-21 Thread David Handy
On Wed, Sep 21, 2005 at 09:31:41AM -0700, Kirby Urner wrote: Mine original draft makes sense to set the stage, cuz the reasoning is so dang primitive. Yours adds a layer of sophistication more reflective of how real world programmers learn to squeeze the most out of their cycles. Your

Re: [Edu-sig] Brute force solutions

2005-09-21 Thread John Zelle
David Handy wrote: On Wed, Sep 21, 2005 at 09:31:41AM -0700, Kirby Urner wrote: Mine original draft makes sense to set the stage, cuz the reasoning is so dang primitive. Yours adds a layer of sophistication more reflective of how real world programmers learn to squeeze the most out of their

[Edu-sig] Brute force solutions

2005-09-20 Thread Kirby Urner
Per my 'Pentagon math' thread, I think the golden ratio (phi) is an important one to explore in K-12.[1] It's one of those key nodes in our curriculum network. Given a regular pentagon, the ratio of a diagonal to an edge is phi. In other words, that famous pentacle pattern is phi-edged,