zephyr

bartoszek/zephyr

Fork 0

Commit Graph

Author	SHA1	Message	Date
Lawrence King	7dae27a90d	libc: minimal: math sqrt: sqrtf: fix numeric accuracy of sqrt and sqrtf. Changed initial guess from a simple x/3 to dividing the exponent by 2. This makes large or small numbers like 10e10 and 01e-10 converge in a few loops. Added a loop counter to ensure that the algorithm breaks out of the loop in the case that the algorithm doesn't converge (toggling between two numbers). Added test cases for sqrt and sqrtf in libc. Tested with a range of numbers between 10e10 and 10e-10. Verify good accuracy in test case. Closes: #55962 Signed-off-by: Lawrence King <lawrencek52@gmail.com>	2023-07-14 12:42:41 -04:00
Andrei Emeltchenko	3074b5808e	libc: sqrtf: Remove dead assignment Remove dead assignment from sqrtf(). Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>	2022-06-05 14:49:31 +02:00
Keith Packard	05946ed9b2	lib/libc/minimal: Move sqrt/sqrtf from samples The lmp90100_evb sample included an implementation of double sqrt, and the on_off_level_lighting_vnd_app sample included an implementation of float sqrtf. Move that code into minimal libc instead of requiring applications to hand-roll their own version. Signed-off-by: Keith Packard <keithp@keithp.com>	2022-05-14 08:49:36 +09:00

Author

SHA1

Message

Date

Lawrence King

7dae27a90d

libc: minimal: math sqrt: sqrtf: fix numeric accuracy of sqrt and sqrtf.

Changed initial guess from a simple x/3 to dividing the exponent by 2.
This makes large or small numbers like 10e10 and 01e-10 converge in a few
loops.

Added a loop counter to ensure that the algorithm breaks out of the loop in
the case that the algorithm doesn't converge (toggling between two
numbers).

Added test cases for sqrt and sqrtf in libc. Tested with a range of numbers
between 10e10 and 10e-10. Verify good accuracy in test case.

Closes: #55962

Signed-off-by: Lawrence King <lawrencek52@gmail.com>

2023-07-14 12:42:41 -04:00

Andrei Emeltchenko

3074b5808e

libc: sqrtf: Remove dead assignment

Remove dead assignment from sqrtf().

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>

2022-06-05 14:49:31 +02:00

Keith Packard

05946ed9b2

lib/libc/minimal: Move sqrt/sqrtf from samples

The lmp90100_evb sample included an implementation of double sqrt, and the
on_off_level_lighting_vnd_app sample included an implementation of float
sqrtf. Move that code into minimal libc instead of requiring applications
to hand-roll their own version.

Signed-off-by: Keith Packard <keithp@keithp.com>

2022-05-14 08:49:36 +09:00

3 Commits