Datamatrix object (Multivariate Analysis Toolbox for MatlabŪ)

written by: Liran Carmel

Last modified: 14:53, Mon 6-Sep-2010

General Description
This object describes a single matrix entity holding related information. This object is meant to define a framework for a single-matrix entity, from which more specialized objects are derived using inheritance. In particular, three main types of data matrices are supported - variables-by-samples (vsmatrix), samples-by-samples (ssmatrix), and variables-by- variables (vvmatrix).

Navigate to:     General Description     Class Structure     Class Construction     Class Functions

Class Structure
Each field can be accessed by the dot (.) operation, or by the GET function. The GET function can work on multiple instances simultaneously. Most fields, except for those that are Dependent, can be modified using the dot (.) operation, or by the SET function.
    Field Description Type Default Dedicated Get/Set Function  
    name name of object, should be short and used as identifier. This field will never be empty. string 'unnamed'    
    description verbal description of the class content. string ''    
    source verbal description of the source of information. string ''    
    row_name Name of the row-category (for example, in gene arrays it can be "tissue"). string ''    
    row_sampleset A sampleset describing the row-samples. sampleset []    
    row_groupings grouping objects associated with the row-samples. grouping array []    
    col_name Name of the column-category (for example, in gene arrays it can be "genes"). string ''    
    col_sampleset A sampleset describing the column-samples. sampleset []    
    col_groupings grouping objects associated with the column-samples. grouping array []    
    matrix the data matrix. double []    
    transformations keeping track on transformations that had been applied previously on the matrix. structure []    
  Dependent no_rows number of row-samples. integer scalar 0 norows  
  Dependent no_cols number of column-samples. integer scalar 0 nocols  

Class Construction
Empty instance (scalar)
an empty datamatrix instance, with all fields initialized to their default values.
syntax: dm = datamatrix;
Empty instance (matrix)
a vector of empty datamatrix instances.
syntax: dm = datamatrix(size);
Copy constructor
one datamatrix instance is copied into another.
syntax: dm_destination = datamatrix(dm_origin);
Construction by field names
an instance is formed by directly providing field values. Any field which is not dependent is permitted.
syntax: dm = datamatrix(field_name, field_value, ...);

List of Functions


displays class content.

Information extraction:

finds the IDs of a list of column-variables.
finds the IDs of a list of row-variables.

SET/GET functions:

retrieves the column-variable names.
get method
retrieves the number of columns in DATAMATRIX instances.
retrieves the number of rows in DATAMATRIX instances.
retrieves the row-variable names.
set method


eliminate columns from a DATAMATRIX instance.
eliminate rows from a DATAMATRIX instance.
selects a subsets of samples in a specific order.