More Features #1

The guide is not complete. More planned features:

• cross product
• tensor product
• delta
• dot product
  • common patterns like clamped dot product with angled brackets too specific I think
• indefinite integral
• ƒ - function
• Heaviside function (step()) possibly too specific; already have sgn
• common patterns like greek letters vs latin ?

And generally:

• converting some complex/intimidating expressions into code
• notation-to-code examples from real papers (e.g. graphics programming papers)