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 02-12-2013, 10:53 PM #1 Soulkeeper Diamond Member     Join Date: Nov 2001 Posts: 5,613 Understanding wiki math image I asked somewhere else, but got no response. Maybe someone here can help me understand this image. When solving for a particular value of i where i == digit, am I correct in converting that image to this ? answer = 1/16^digit * (4/8*digit+1 - 2/8*digit+4 - 1/8*digit+5 - 1/8*digit+6) is a multiplication implied with number(number) in that image ? thanks __________________ A8-3870 @3.3GHz 1.3125v 16GB 1866 9-9-9-23 1.35v Linux software/gaming exclusively linuxsociety.org Afraid to buy radeons because they might be voltage locked. I want to lower/raise voltages with ADL.
 02-12-2013, 11:08 PM #2 Vectronic Senior Member   Join Date: Jan 2013 Posts: 470 Minor correction (should be): (1/(16^i)) * (4/(8*i+1) - 2/(8*i+4) - 1/(8*i+5) - 1/(8*i+6)) Otherwise you would be doing (4/8) * (i+1)... which would be wrong. And yes, excluding the first those appear to be multiplications rather than exponents.
 02-12-2013, 11:18 PM #3 Soulkeeper Diamond Member     Join Date: Nov 2001 Posts: 5,613 Thanks, but even with the extra parenthesis and correct order of precedence, i'm still getting a wrong result. ie: for i = 5 answer = 9.5367431640625e-07 * (0.097561 - 0.045455 - 0.022222 - 0.021739) insanely small number. As this formula is supposed to calculate a digit (i) of pi, the 5th digit should be 9. Unless i'm understanding this wrong ? url to formula explanation __________________ A8-3870 @3.3GHz 1.3125v 16GB 1866 9-9-9-23 1.35v Linux software/gaming exclusively linuxsociety.org Afraid to buy radeons because they might be voltage locked. I want to lower/raise voltages with ADL.
 02-12-2013, 11:33 PM #4 serpretetsky Senior Member     Join Date: Jan 2012 Posts: 226 http://www.math.hmc.edu/funfacts/ffiles/20010.5.shtml not familiar with this equation, but it looks like it should work just like you want.... except it's in hexadecimal (hence the reason you see 1/16th at the front, and not 1/10th).
 02-12-2013, 11:41 PM #5 Soulkeeper Diamond Member     Join Date: Nov 2001 Posts: 5,613 base 16 ... that explains the confusions __________________ A8-3870 @3.3GHz 1.3125v 16GB 1866 9-9-9-23 1.35v Linux software/gaming exclusively linuxsociety.org Afraid to buy radeons because they might be voltage locked. I want to lower/raise voltages with ADL.
02-12-2013, 11:58 PM   #6
Vectronic
Senior Member

Join Date: Jan 2013
Posts: 470

Ahh yeah, the Wiki you were reading kind of separates the Hexidecimal part... I thought you were looking at this which says
Quote:
 This formula, unlike others before it, can produce any individual hexadecimal digit of π without calculating all the preceding digits

 02-13-2013, 12:11 AM #7 Soulkeeper Diamond Member     Join Date: Nov 2001 Posts: 5,613 thanks guys __________________ A8-3870 @3.3GHz 1.3125v 16GB 1866 9-9-9-23 1.35v Linux software/gaming exclusively linuxsociety.org Afraid to buy radeons because they might be voltage locked. I want to lower/raise voltages with ADL.