How to perform median filtering considering window?

hello, i need to perform filteration on raw ECG signal using median filter and then use Butterworth filter on that. but im not supposed to use medfilt2, buttord or those functions in matlab. How to create my own function? im not sure on how to do it.Can someone help me in this? I am totally new in this MATLAB. i am trying my best to cope up. Thanks in advance. here is my abnormal ECG file.

[jonas]

You should start by reading about medfilt2 in the doc and understand how it works. You can also check movmean , as it has some nice images on how windows work on 1D-arrays.

I assume this is homework?

[Image Analyst]

Are you allowed to use any functions that might help, like sort() and med()?

http://www.mathworks.com/matlabcentral/answers/8626-how-do-i-get-help-on-homework-questions-on-matlab-answers

http://www.mathworks.com/matlabcentral/answers/38787-what-can-be-programmed-without-any-built-in-functions