The following worked for both a Debian Sarge box, and an Xubuntu laptop. I hope it saves someone some grief.

$ dpkg -l | grep magick
  ii  imagemagick    6.0.6.2-2.7    Image manipulation programs
  ii  libmagick6     6.0.6.2-2.7    Image manipulation library
  ii  perlmagick     6.0.6.2-2.4    A perl interface to the libMagick
  ii  rubymagick     0.1.3-13       Ruby interface for ImageMagick

Get rid of the rubymagick package

$ apt-get remove --purge rubymagick

Install the dev versions of libmagick6 and Ruby 1.8 edit: for Xubuntu, install libmagick9

$ apt-get install libmagick6-dev ruby1.8-dev

Install rmagick from the gem

$ gem install rmagick

You can test the install by running a simple app like this, which will print the EXIF data from an image:

require 'rubygems'
require 'RMagick'

require 'pp'

img = Magick::Image.read('test.jpg').first
exif_data = img.get_exif_by_entry()

pp exif_data

Update:

As of Xubuntu 7.04 (Feisty Fawn), you need libmagick9-dev.

var aString = "kb" + 63; // results in string "kb63"

Sometimes, you really need a string or a number. For example, you might have a database key that you want to use as an array index:

var dbKey = 546735289; // some surrogate key out of the database.
var dbObject = {
   name: "Kenneth",
   age: "old",
   likes: "beer"
};
var theArray = new Array();
theArray[dbKey] = dbObject;

But now, theArray.length is 546735290 – one more than the index. Javascript arrays are sparse, so this might not cause any memory problems since memory should only be allocated for the single array element at 546735289. However, if you loop through the array using a for loop theArray.length times, performing some expensive operation inside the loop – such as a complex DOM manipulation – you might get into trouble.

In this case, you’d be better off using a named property instead of a numeric array index. To convert a number to a string:

    // use the toString method
    dbKey.toString

    // use the String() constructor
    String(dbKey)

    // concatenate a number with empty string. Crude and ugly
    dbKey + ""

What if you want to go the other way, from a string to a number? The cheap and easy way is to do some math on the string:

    var myString = "1000";
    var myNumber = myString * 1

Don’t try and use the + operator:

    // won't work. javascript thinks concatenate
    var myString = "1000";
    var myNumber = myString + 0; // results in the string 10000