can anyone give me the matlab code for extraction of p wave from an ecg signal

i am doing my assingment .your help would be greatly appreciated.the aim is to remove all the other parts of the signal and only keep the p wave

[Walter Roberson]

What have you done on your homework?

[Youssef Khmou]

besides, give a simple example so as to build on it,

[Rahul]

downloaded the signals from physionet