It is a problem of communication that ask you utilize Fourier Series to create a periodic rectangular wave with the frequency of 1000Hz. I'd like to fullfill it using Matlab which I have never come accross before. I hope this is a nice work and i began yesterday. It is easy in fact, however, there seems something wrong with the function of integral. As you know, we must do the integral when we work out the fourier series of any function. I have tryed almost every method but it didn't work still.

It is Lao Zhu who helped me to work out this problem. He didn't use the systme function of integral at all but do integral by all his own codes. And it worked very well. But I am still puzzlled that: where i was wrong? Maybe only the God knows.

Two days later is the new year 2006 coming. Our class decide to have a celebrating dinner party this evening at the Guolin Restaurant. 52 of our 59 classmembers go for it and we have a even big dinner. The food tastes good and we all have a good time together. I hope everyone go smoothly in the coming year and have a great progress. Bottoms up!