Potential Library Problem/Error Message for my first advanced project

Hello Arduino Friends,

I am working on an arduino project for which the link is here:

I keep getting the following error message and I'm not at all sure what to do. This looks like such a great project. I've come so far and I'm a little befuddled. If anyone could help I would so so so appreciate it! Thanks so much!

Error message:

Arduino: 1.5.8 (Mac OS X), Board: "Arduino Uno"

/Users/Kerem/Documents/Arduino/libraries/Fix_fft/fix_fft.cpp:50:7: error: 'prog_int8_t' does not name a type
const prog_int8_t Sinewave[N_WAVE-N_WAVE/4] PROGMEM = {
^
In file included from /Users/Kerem/Documents/Arduino/libraries/Fix_fft/fix_fft.cpp:1:0:
/Users/Kerem/Documents/Arduino/libraries/Fix_fft/fix_fft.cpp: In function 'int fix_fft(char*, char*, int, int)':
/Users/Kerem/Documents/Arduino/libraries/Fix_fft/fix_fft.cpp:199:28: error: 'Sinewave' was not declared in this scope
wr = pgm_read_word_near(Sinewave + j+N_WAVE/4);
^
/Users/Kerem/Documents/Arduino/libraries/Fix_fft/fix_fft.cpp:209:28: error: 'Sinewave' was not declared in this scope
wi = -pgm_read_word_near(Sinewave + j);
^
Error compiling.

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In version 1.6.0, the "prog_int8_t" is no longer used. Replace it with "const int8_t".
Explanation about PROGMEM use is here : Gammon Forum : Electronics : Microprocessors : Putting constant data into program memory (PROGMEM)

Peter_n:
In version 1.6.0, the "prog_int8_t" is no longer used. Replace it with "const int8_t".
Explanation about PROGMEM use is here : Gammon Forum : Electronics : Microprocessors : Putting constant data into program memory (PROGMEM)

I'm not sure how to do that? If I am to edit my library then for some reason i am being blocked to do that.

photosynthetics:
If I am to edit my library then for some reason i am being blocked to do that.

What do you mean blocked. There is nothing stopping you from opening the .h and .cpp files from the library and editing it.

In your own “Documents” folder is a folder “Arduino”, that is where you need to go. You will see all your projects there and also a folder “libraries”. In the folder “libraries”, go to the folder “Fix_fft” and edit “fix_fft.cpp” to change the “prog_int8_t”.

/Users/<[i]user[/i]>/Documents/Arduino/libraries/Fix_fft/fix_fft.cpp