dylan

Always interesting to see if someone can write a great linear algebra book. I like Axler's "Linear Algebra Done Right" [1] because he puts off the determinant until it's clear why you want to define such a map. That the book continually treats the case when your field is the complex numbers slows things down at times, though.

[1] http://linear.axler.net

This is now in the Ruby 1.9 core:

http://www.ruby-doc.org/core-1.9/classes/Object.html#M000309

Sellers can't leave anything but positive feedback these days. I imagine the next step is for the system to add those "fast payment good ebayer AA+++" lines to your profile whenever you do anything.

If you have hosting, Chyrp is an interesting newcomer:

http://chyrp.net

Of course, one of the common knocks on Ruby is that naively referring to a function executes it, and to pass functions around avoiding

  list.map { |i| process i }

one must write

  list.map &method(:process)

or, as the Rails guys have done [1], open up Symbol#to_proc so that

  list.map &:process

works. This will be part of core Ruby in 1.9, but last I heard it's slow [2].

[1] http://github.com/rails/rails/tree/master/activesupport/lib/...

[2] http://www.ruby-forum.com/topic/161089

Not sure why they didn't link the article instead:

http://www.motherjones.com/news/feature/2008/07/slammed-cons...

This has been a tough adjustment for those of us who need the entire wait in line to decide on a drink.