How to convert NSdata to float

I've got a C++ method for audio processing which accept float 2d array. I have written a wrapper method using objective c for that method.

Now I need to convert audio file from objective c and send that audio data for that method.

Ive converted one of the audio file to NSdata using the below code

NSString *filePath = [[NSBundle mainBundle] pathForResource:@"adaharem" ofType:@"mp3"];
NSData *data = [NSData dataWithContentsOfFile:filePath];

How can I convert this NSdata to float 2d array in objective c ?