will be assumed to return id

I import oourafft.h and oourafft.m class, but get strange error while ooura initialize.

OouraFFT * myFFT = [OouraFFT initForSignalsOfLength:1024 numberOfWindows:10];

OouraFFT may not respond to +initForSignalsOfLength: numberOfWind开发者_开发知识库ows

Messages without matching method signature will be assumed to return 'id' and accept argument - Warning

I think that it some kind of error import .h file

You are trying to call class method which does not exist in OouraFFT - this method is instance method, so you need to allocate object at first.

You should do the following:

OouraFFT * myFFT = [[OouraFFT alloc] initForSignalsOfLength:1024 andNumWindows:10];

And don't forget that you own object after this, therefore you should release or autorelease in an appropriate place.