I am a newbie Mathematica user, writing (if I may say so myself) a very, very, very difficult assignment about fractals.
I have a couple of questions:
1) Patterns... for instance: f[x_Integer,y_?ListQ]:= x+y
What is the difference between x_List, x_?List & x_?ListQ ? And how do I know which one to use? Not just when using List as a pattern, but also NumericQ, Positive etc...
2) Which pattern should I use, if I want to restrict a certain variable, so that only positive integers were allowed?
3) Are there any mathematica stylesheet resources on the web.. like different stylesheets I could download ? - is the stylesheet "incorporated" in the notebook, or do I have to send it along as a separate file, when handing in an assignment?
Thx in advance!