Yeah man, I am trying to keep on writing here, but there is a sum of factors like homeworks in addition I don't have internet in my home, so it is being very difficult. Surprisingly I realise everyday I learnt a lot from this site. I would like to increase my presence in Diff Eq forum, and in Mech&Aeros forum, which are my two favourite areas, besides wasting my time in G.D. . The truth is that the weather in San Diego is wonderful. While in Madrid the temperature is about 5ºC, here the sun shines everyday. Great! COOOOOOOL!