Dewey Decimal Classification tools

a collection of tools to work w/ Dewey Decimal call numbers

some terminology explanation

To the best of my (admittedly lacking) knowledge, there is no set terminology to differentiate the whole numbers from the decimals in a Dewey Decimal System call number. Internally, the following terms are used to refer to the different parts:

For the call number DVD 741.4372 A123b c.2 v.3 2004:

term     | value

-------------|------ prestamp | DVD major | 741 minor | 4372 cutter | A123b additional | c.2 v.3 2004 call number| 741.4372

What's also a bit confusing is the differentiation between a call number and a CallNumber object. Unless specifically referencing the CallNumber object's $callNumber field, the camel-cased CallNumber refers to the object and lower-cased call number refers to the major/minor combination.

Please add an issue if you've got some suggestions re: clearing the code up!

usage

The Dewey class has a few static methods for general use:

Dewey::calculateRange($rangeString)

Calculate the range of DDS call numbers using an * to specify where the range takes place. Returns a tuple array of [$min, $max]

example

$drawing = Dewey::calculateRange("74*");
// returns `array("740", "750")`

range string	returned array
7**	["700", "800"]
74*	["740", "750"]
741.*	["741", "742"]
741.4*	["741.4", "741.5"]

Dewey::compare($input, $comparison, $operator[, $includePrestamp = false])

Compare $input to $comparison using $operator. Accepts: <, >, <=, >=, ==, ===. $includePrestamp will involve the prestamp in the comparison. Returns a boolean.

example

var_dump(Dewey::compare("741.4372 A123x", "750", "<"));
// bool(true)

Dewey::parseCallNumber($callNumberString)

Builds a Dewey\CallNumber object from the provided string.

example

var_dump(Dewey::parseCallNumber("741.4372 A123x"));
// object(Dewey\CallNumber)#2 (3) {
//  ["callNumber":protected]=>
//  string(7) "741.4372"
//  ["cutter":protected]=>
//  string(5) "A123x"
//  ["additional":protected]=>
//  string(0) ""
// }

Dewey\CallNumber

A CallNumber object is a representation of a DDS call number.

An object can be constructed by using Dewey::parseCallNumber or by instantiating a new Dewey\CallNumber with a DDS call number string as a parameter (which uses the former under the hood anyway).

The following methods are available on an instantiated object:

Dewey\CallNumber::compare($comparisonAgainst, $operator)

Compare the instantiated object against another DDS call number (or Dewey\CallNumber object). Returns a bool. The following wrappers are provided too:

• Dewey\CallNumber::equalTo($comp[, $deepEqual = false])
• Dewey\CallNumber::greaterThan($comp)
• Dewey\CallNumber::greaterThanEqualTo($comp)
• Dewey\CallNumber::lessThan($comp)
• Dewey\CallNumber::lessThanEqualTo($comp)

Dewey\CallNumber::inRange($range[, $lessThanEqualTo = true])

Whether the instantiated object falls within the range provided as a range string (see Dewey::calculateRange for examples) or a min/max tuple. If $lessThanEqualTo is false, does not include the $max value as true.

license

MIT