Re: Anyone else notice __ieee754_sqrt() is missing from libm
Posted:
Tue Apr 21, 2015 4:22 pmby jcmvbkbc
Kevin Uhlir (N0BEL) wrote:People say its slower, that may be, but I can get, for example, over 10,000 sin() calculations per second, which is well fast enough for what I'm working on.
It's slower (by factor of 12..13) only for the first time. When code gets to the FLASH mapping cache it runs as fast as from IRAM. If your loop is tight enough to fit into 32KBytes of FLASH cache it should be fast.
Re: Anyone else notice __ieee754_sqrt() is missing from libm
Posted:
Tue Apr 21, 2015 9:15 pmby Kevin Uhlir (N0BEL)
I think it will work well for my application.
I'll be publishing it on github when i'm done.
/Kevin
Re: Anyone else notice __ieee754_sqrt() is missing from libm
Posted:
Thu Apr 23, 2015 1:53 pmby viccc
I want to use atan and sqrt
I rebuild compiler branch lx106-g++, but an error happens
build/app_app.a(user_main.o):(.irom0.text+0xe0): undefined reference to `sqrt'
build/app_app.a(user_main.o):(.irom0.text+0xe8): undefined reference to `atan'
Can you tell me the steps to use this functions?
Thanks
Re: Anyone else notice __ieee754_sqrt() is missing from libm
Posted:
Fri Apr 24, 2015 1:16 pmby jcmvbkbc
viccc wrote:build/app_app.a(user_main.o):(.irom0.text+0xe0): undefined reference to `sqrt'
build/app_app.a(user_main.o):(.irom0.text+0xe8): undefined reference to `atan'
Start with adding -lm to your linker options to link with math library.