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Groups > comp.lang.forth > #54556
| From | Paul Rubin <no.email@nospam.invalid> |
|---|---|
| Newsgroups | comp.lang.forth |
| Subject | Re: embedded forth |
| Date | 2017-01-30 14:09 -0800 |
| Organization | A noiseless patient Spider |
| Message-ID | <87d1f4yzcs.fsf@nightsong.com> (permalink) |
| References | (5 earlier) <e90a34e0-376e-4910-bd6a-96d8f16bf0bf@googlegroups.com> <o6mla6$f0l$1@dont-email.me> <e8b3a38a-d6b7-41b3-a760-fe07881bdf17@googlegroups.com> <o6nl76$o8v$1@dont-email.me> <d126a340-9abd-4145-99f6-2d01915ebe64@googlegroups.com> |
Ilya Tarasov <ilya74.tarasov@gmail.com> writes:
> From the first look, we may list degrees, minutes and seconds, but is
> it optimal?
It's convenient, so the question then is whether it's close enough.
Optimal involves non-uniform placement of the interpolation points,
e.g. at the so-called Chebychev nodes according to Wikipedia. I'd
expect that with non-optimal placement, you can still get the same
accuracy by using more points. That seems ok to me if you have enough
memory for the bigger tables.
Using naive deg/min/sec interpolation (see below) I get a max error of
about 1.56e-4 which is well above 1 ULP in single precision. I think
that can be improved by just moving the interpolation point slightly.
There's too stuff going on here at the moment for me to figure that out
right now, but this is a start.
================================================================
: dms.1 ( f:x -- f:int f:frac ) fdup f>s s>f ftuck f- ;
: f>dms ( F:degrees -- F:degrees F:minutes F:seconds )
dms.1 60e f* dms.1 60e f* dms.1 f+ ;
: dms>f ( F:d F:m F:s -- F:dd ) 60e f/ f+ 60e f/ f+ ;
: deg>rad ( F:d -- F:rad ) pi f* 180e f/ ;
: rad>deg ( F:rad -- F:deg ) 180e f* pi f/ ;
: min>rad ( F:min -- F:rad ) 60e f/ deg>rad ;
: sec>rad ( F:min -- F:rad ) 60e f/ min>rad ;
\ approximate sin x using d/m/s interpolation
: xsin ( F:deg -- F:approximate sine )
f>dms sec>rad { F: s } min>rad { F: m } deg>rad { F: d }
d fcos m fsin f*
d fsin m fcos f* f+
fdup fcos s f*
f+ ;
: fclearstack fdepth 0 ?do fdrop loop ;
: cs clearstack fclearstack ;
: err ( deg -- e ) fdup xsin fswap deg>rad fsin f/ 1e f- fabs ;
: maxerr ( -- e ) cs 0e 89999 1 do i s>f 1e-3 f* err fmax loop ;
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embedded forth Dale Scott <dalescottnet@gmail.com> - 2017-01-21 11:27 -0800
Re: embedded forth Paul Rubin <no.email@nospam.invalid> - 2017-01-21 11:31 -0800
Re: embedded forth stephen@mpeforth.com - 2017-01-22 00:52 -0800
Re: embedded forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-01-22 17:09 +0000
Re: embedded Forth Dale Scott <dalescottnet@gmail.com> - 2017-01-22 09:43 -0800
Re: embedded Forth stephen@mpeforth.com - 2017-01-22 12:19 -0800
Re: embedded Forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-22 21:25 +0100
Re: embedded Forth john <anon@example.com> - 2017-01-22 21:04 +0000
Re: embedded Forth "Elizabeth D. Rather" <erather@forth.com> - 2017-01-22 12:30 -1000
Re: embedded Forth hughaguilar96@gmail.com - 2017-01-22 20:45 -0800
Re: embedded Forth stephen@mpeforth.com - 2017-01-22 14:08 -0800
Re: embedded Forth Paul Rubin <no.email@nospam.invalid> - 2017-01-22 14:55 -0800
Re: embedded Forth Dale Scott <dalescottnet@gmail.com> - 2017-01-22 20:41 -0800
Re: embedded Forth Paul Rubin <no.email@nospam.invalid> - 2017-01-22 21:19 -0800
Re: embedded Forth hughaguilar96@gmail.com - 2017-01-22 21:36 -0800
Re: embedded Forth Dale Scott <dalescottnet@gmail.com> - 2017-01-22 22:09 -0800
Re: embedded Forth rickman <gnuarm@gmail.com> - 2017-01-23 04:15 -0500
Re: embedded Forth Dale Scott <dalescottnet@gmail.com> - 2017-01-23 08:41 -0800
Re: embedded Forth rickman <gnuarm@gmail.com> - 2017-01-23 14:32 -0500
Re: embedded Forth Dale Scott <dalescottnet@gmail.com> - 2017-01-23 11:53 -0800
Re: embedded Forth rickman <gnuarm@gmail.com> - 2017-01-23 15:10 -0500
Re: embedded Forth Paul Rubin <no.email@nospam.invalid> - 2017-01-23 14:34 -0800
Re: embedded Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-01-24 03:14 -0600
Re: embedded Forth rickman <gnuarm@gmail.com> - 2017-01-23 03:43 -0500
Re: embedded Forth john <anon@example.com> - 2017-01-23 10:32 +0000
keep secrets (was Re: embedded Forth) "Wolfgang Allinger" <all2001@spambog.com> - 2017-01-23 08:58 -0300
Re: keep secrets (was Re: embedded Forth) Rod Pemberton <NeedNotReplyHere@xrsevnneqk.cem> - 2017-01-23 07:47 -0500
Re: keep secrets (was Re: embedded Forth) "Wolfgang Allinger" <all2001@spambog.com> - 2017-01-23 18:18 -0300
Re: keep secrets (was Re: embedded Forth) rickman <gnuarm@gmail.com> - 2017-01-23 19:15 -0500
Re: keep secrets (was Re: embedded Forth) rickman <gnuarm@gmail.com> - 2017-01-23 14:38 -0500
Re: keep secrets (was Re: embedded Forth) "Wolfgang Allinger" <all2001@spambog.com> - 2017-01-23 18:43 -0300
Re: keep secrets (was Re: embedded Forth) rickman <gnuarm@gmail.com> - 2017-01-23 19:48 -0500
Re: keep secrets (was Re: embedded Forth) "Elizabeth D. Rather" <erather@forth.com> - 2017-01-23 16:30 -1000
Re: keep secrets (was Re: embedded Forth) rickman <gnuarm@gmail.com> - 2017-01-23 22:23 -0500
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-22 13:44 -0500
Re: embedded forth Paul Rubin <no.email@nospam.invalid> - 2017-01-22 13:38 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-23 00:45 -0500
Re: embedded forth Dale Scott <dalescottnet@gmail.com> - 2017-01-22 22:44 -0800
Re: embedded forth Paul Rubin <no.email@nospam.invalid> - 2017-01-23 00:48 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-23 03:51 -0500
Re: embedded forth john <anon@example.com> - 2017-01-23 10:02 +0000
Re: embedded forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-01-23 09:01 +0000
Re: embedded forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-23 13:05 +0100
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-23 14:40 -0500
Re: embedded forth Mark Wills <markwills1970@gmail.com> - 2017-01-24 01:12 -0800
Re: embedded forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-24 14:38 +0100
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-24 19:51 -0500
Re: embedded forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-25 11:34 +0100
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-25 22:13 -0500
Re: embedded forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-26 11:36 +0100
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-26 14:07 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-26 00:19 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-26 14:15 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-27 13:08 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-27 17:54 -0500
Re: embedded forth Paul Rubin <no.email@nospam.invalid> - 2017-01-27 15:29 -0800
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-27 16:28 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-27 23:58 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-28 11:58 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-28 15:36 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-28 15:05 -0800
Re: embedded forth Paul Rubin <no.email@nospam.invalid> - 2017-01-28 15:57 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-28 21:51 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-29 09:53 -0800
Re: embedded forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-29 19:32 +0100
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-29 11:53 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-30 01:10 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-29 23:11 -0800
Re: embedded forth Paul Rubin <no.email@nospam.invalid> - 2017-01-29 23:34 -0800
Re: embedded forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-30 12:42 +0100
Re: embedded forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-30 12:36 +0100
Re: embedded forth ctmalan@gmail.com - 2017-01-30 11:02 -0800
Re: embedded forth Paul Rubin <no.email@nospam.invalid> - 2017-01-30 11:04 -0800
Re: embedded forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-01-31 04:34 -0600
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-30 12:15 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-30 10:15 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-30 12:20 -0800
Re: embedded forth Paul Rubin <no.email@nospam.invalid> - 2017-01-30 14:09 -0800
Re: embedded forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-31 03:04 +0100
Re: embedded forth Paul Rubin <no.email@nospam.invalid> - 2017-01-30 20:19 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-30 17:10 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-30 14:38 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-30 23:09 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-31 09:32 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-02-08 18:22 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-09 01:46 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-02-09 05:11 -0500
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-02-12 01:30 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-12 10:21 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-02-12 19:37 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-14 13:26 -0800
Re: embedded forth Gary Bergstrom <forthprgrmr@gmail.com> - 2017-02-14 11:36 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-02-14 18:13 -0500
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-28 21:51 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-29 10:20 -0800
Re: embedded forth Cecil Bayona <cbayona@cbayona.com> - 2017-01-29 12:38 -0600
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-01-29 11:49 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-02-04 04:22 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-04 17:54 -0800
Re: embedded forth hughaguilar96@gmail.com - 2017-02-04 20:26 -0800
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-05 07:53 -0800
Re: embedded forth hughaguilar96@gmail.com - 2017-02-05 11:08 -0800
Re: embedded forth hughaguilar96@gmail.com - 2017-02-05 11:39 -0800
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-08 06:46 -0800
Re: embedded forth luser droog <mijoryx@yahoo.com> - 2017-02-13 19:17 -0800
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-15 06:23 -0800
Re: embedded forth hughaguilar96@gmail.com - 2017-02-15 11:09 -0800
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-15 15:24 -0800
Re: embedded forth jkn_gg@nicorp.f9.co.uk - 2017-02-16 09:49 -0800
Re: embedded forth hughaguilar96@gmail.com - 2017-02-17 09:12 -0800
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-17 12:47 -0800
Re: embedded forth hughaguilar96@gmail.com - 2017-02-17 16:18 -0800
Re: embedded forth luser droog <mijoryx@yahoo.com> - 2017-02-16 08:43 -0800
Re: embedded forth Alex <alex@rivadpm.com> - 2017-02-05 20:47 +0000
Re: embedded forth hughaguilar96@gmail.com - 2017-02-05 13:36 -0800
Re: embedded forth Alex <alex@rivadpm.com> - 2017-02-05 23:18 +0000
Re: embedded forth hughaguilar96@gmail.com - 2017-02-05 21:10 -0800
Re: embedded forth Alex <alex@rivadpm.com> - 2017-02-06 11:12 +0000
Re: embedded forth hughaguilar96@gmail.com - 2017-02-05 21:15 -0800
Re: embedded forth hughaguilar96@gmail.com - 2017-02-05 22:45 -0800
Re: embedded forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-02-06 12:04 +0100
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-08 03:08 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-02-08 06:39 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-08 07:15 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-02-08 15:49 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-09 01:14 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-02-09 05:19 -0500
Re: embedded forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-02-09 03:48 -0800
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-02-05 16:08 -0500
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-02-07 21:59 -0500
Re: embedded forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-28 11:10 +0100
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-28 06:15 -0500
Re: embedded forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-28 19:48 +0100
Re: embedded forth rickman <gnuarm@gmail.com> - 2017-01-28 14:37 -0500
Re: embedded forth mhx@iae.nl - 2017-01-28 07:48 -0800
Re: embedded forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-28 19:53 +0100
Re: embedded forth mhx@iae.nl - 2017-01-28 15:49 -0800
Re: embedded forth "Wolfgang Allinger" <all2001@spambog.com> - 2017-01-23 18:46 -0300
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