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contiki-os / contiki

The official git repository for Contiki, the open source OS for the Internet of Things
http://www.contiki-os.org/
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Implementating exponential function #2662

Open vishal623 opened 4 years ago

vishal623 commented 4 years ago

Hello,

I want to implement a sigmoid equation in the er-coap application. But the biggest challenge is the exponential function.

I have found the msp430-gcc supports some expf() function but I did not find it in Contiki.

Can anyone guide me on how can I implement exp() in er-coap or any application?

atiselsts commented 4 years ago

What exactly is your problem? Did you trying adding #include <math.h> and linking with libm to your application? For the latter, add TARGET_LIBFILES += -lm to the Makefile.

vishal623 commented 4 years ago

I did try this long back with contiki-3.0 but solution did not work.

I am using msp430-gcc-4.6.3 toolchain. And I did not find any "libm.a" in the folder which include exp or expf function.

Whether adding TARGET_LIBFILES += -lm in the Makefile, is it work?

vishal623 commented 4 years ago

And one more thing, I am planning to add it in the code of apps/er-coap/er-coap-transactions.c. Not in example folder.

vishal623 commented 4 years ago

I want to apply sigmoid function, so power function is also required. Is "^" works in Contiki?