(Plus 42) Fraction approximation equation - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: Not HP Calculators (/forum-7.html) +--- Forum: Not quite HP Calculators - but related (/forum-8.html) +--- Thread: (Plus 42) Fraction approximation equation (/thread-18047.html) (Plus 42) Fraction approximation equation - Vincent Weber - 02-17-2022 01:38 PM Hi all, Since Plus42 does not (have) yet a fraction mode à la 32SII/35S, and since this mode is anyway limited (4096 denominator maximum, no expression of tolerance, just max denominator) I made an equation for it. It has no intelligence whatsoever, no limited fractions algorithm, just plain stupid brute force try of every possible denominator. Plus42 is so fast anyway :) Just enter X, the value to be approximated, and TOL (e.g. 1E-8), the tolerance of the approximation. Press EVAL, now N holds the numerator of the approximated fraction, D the denominator, and RES the difference with the original number. Cheers FRAC:0×FOR(SEQ(L(N:IP(X)):L(D:1)):L(RES:ABS(N÷D-X))>TOL:0:SEQ(L(D:D+1):L(N:RND(D×X:0))))+RES RE: (Plus 42) Fraction approximation equation - Thomas Okken - 02-17-2022 02:14 PM (02-17-2022 01:38 PM)Vincent Weber Wrote:  FRAC:0×FOR(SEQ(L(N:IP(X)):L(D:1)):L(RES:ABS(N÷D-X))>TOL:0:SEQ(L(D+1):L(N:RND(D×X:0))))+RES You can prevent :‌D from turning into by putting a zero-width space or a zero-width non-joiner between the : and the D. (The difference is whether a line break may occur or not.) https://unicode-table.com/en/200B/ https://unicode-table.com/en/200C/ RE: (Plus 42) Fraction approximation equation - Massimo Gnerucci - 02-17-2022 02:50 PM (02-17-2022 02:14 PM)Thomas Okken Wrote:   (02-17-2022 01:38 PM)Vincent Weber Wrote:  FRAC:0×FOR(SEQ(L(N:IP(X)):L(D:1)):L(RES:ABS(N÷D-X))>TOL:0:SEQ(L(D:D+1):L(N:RND(D×X:0))))+RES You can prevent :‌D from turning into :D by putting a zero-width space or a zero-width non-joiner between the : and the D. (The difference is whether a line break may occur or not.) https://unicode-table.com/en/200B/ https://unicode-table.com/en/200C/ Isn't it simpler to just "Disable Smilies"? RE: (Plus 42) Fraction approximation equation - Vincent Weber - 02-17-2022 03:47 PM (02-17-2022 02:50 PM)Massimo Gnerucci Wrote:   (02-17-2022 02:14 PM)Thomas Okken Wrote:  You can prevent :‌D from turning into by putting a zero-width space or a zero-width non-joiner between the : and the D. (The difference is whether a line break may occur or not.) https://unicode-table.com/en/200B/ https://unicode-table.com/en/200C/ Isn't it simpler to just "Disable Smilies"? Thanks Thomas and Massimo, I didn't notice that ! Since I'm lazy, I chose the "disable smilies" option Cheers RE: (Plus 42) Fraction approximation equation - ijabbott - 02-17-2022 08:38 PM (02-17-2022 02:50 PM)Massimo Gnerucci Wrote:   (02-17-2022 02:14 PM)Thomas Okken Wrote:  You can prevent :‌D from turning into by putting a zero-width space or a zero-width non-joiner between the : and the D. (The difference is whether a line break may occur or not.) https://unicode-table.com/en/200B/ https://unicode-table.com/en/200C/ Isn't it simpler to just "Disable Smilies"? Disabling smilies is also better for cut and pasting.