This module defines the abstract super-classes for the components that go into character matrices. In nexml instance documents, the <characters> element structure forms the concrete instance of the complex types defined here. The concrete structure consists of one <format> structure that define allowed states, their symbols and ambiguity mappings, and the matrix columns they apply to. This is then followed by a <matrix> element that contains rows that either consist of granular cells with individual states, or of compact sequences. The AbstractMapping type is the superclass for an ambiguity mapping. In an instance document, a subclass of this type will look like <member state="st1"/>, i.e. an element called "member" with an attribute called "state" whose value is an id reference that refers to an element that subclasses AbstractState. The purpose of AbstractMapping is to specify which other states may be implied, e.g. a nucleotide symbol "N" would have mappings to "A", "C", "G" and "T". AbstractSymbol is a simple type, i.e. a string token. Concrete subclasses of character blocks will restrict AbstractSymbol to something sensible such as a regular expression of IUPAC symbols, a range of integer values, and so on. The AbstractState type is the super-class for a state definition. The element has a required symbol attribute that in restricted concrete subclasses must be of a sensible type such as a single IUPAC character. It may enclose zero or more AbstractMapping elements to resolve ambiguities. The AbstractUncertainStateSet type is the super-class for an uncertain state set definition. The element has a required AbstractSymbol attribute that in restricted concrete subclasses must be of a sensible type such as a single IUPAC character. It may enclose zero or more AbstractMapping elements to resolve ambiguities. The AbstractPolymorphicStateSet type is the super-class for a polymorphic state set definition. The element has a required AbstractSymbol attribute that in restricted concrete subclasses must be of a sensible type such as a single IUPAC character. It may enclose zero or more AbstractMapping elements to resolve ambiguities. A container for a set of AbstractState elements. The CodonPosition type is an integer with value 1, 2 or 3, used in DNA and RNA. The MSTokenLength simple type is used to specify, per column, how many tokens may occur in a multistate single observation matrix. For example, in a matrix where every cell holds a vector of two continuous values (say, mean and standard deviation of a measurement), the column definition provides a hint to this effect, by setting the attribute tokens="2" The AbstractChar type is the superclass for a column definition, which may have a "states" attribute that refers to an AbstractStates element, a codon attribute of type CodonPosition and an id attribute that may be an actual id (e.g. for categorical matrices where observations explicitly refer to a column definition) or an integer for sequence matrices. Character The AbstractFormat type is the superclass for the element that defines the allowed characters and states in a matrix, and their ambiguity mapping. It may enclose AbstractStates elements that define states and their mappings, and AbstractChar elements that specify which AbstractStates apply to which matrix columns. The AbstractObs type is the superclass for single observations, i.e. cells in a matrix. A concrete instance of AbstractObs has a "char" attribute that refers to an explicitly defined character (e.g. in categorical matrices), and a "state" attribute that either holds a reference to an explicitly defined state, or a raw state value (a continuous value). Character_State_Datum AbstractSeq is a simple type based on xs:string. Concrete subclasses must restrict this type to something more sensible, such as a regular expression for IUPAC single character symbols, or whitespace separated integers or doubles. AbstractTokenList is a simple type superclass for a compact character data representations that consist of space-separated lists of tokens. Examples of this are continuous character data (where the compact representation is a list of space-separated floating point numbers) and standard categorical data (which is represented as integers, which can be > 9, and hence need to be space-separated). The AbstractSeqRow represents a single row in a matrix. The row must refer to a previously declared otu element by its id attribute (and must have an id itself, may have a label, and may have meta attachments). The row contains a single seq element with raw character data. The AbstractObsRow represents a single row in a matrix. The row must refer to a previously declared otu element by its id attribute (and must have an id itself, may have a label, and may have meta attachments). The row contains multiple cell elements. The AbstractSeqMatrix super class is the abstract type for a <matrix> element that contains rows which hold raw character sequences. The AbstractObsMatrix super class is the abstract type for a <matrix> element that contains rows which hold granular state observations. The AbstractBlock is the superclass for blocks that contain an element structure of type AbstractFormat. The AbstractSeqBlock type is the superclass for character blocks that consist of raw character sequences. The AbstractSeqBlock type is the superclass for character blocks that consist of granular character state observations.