MetaData
Metadata from microarray experiment
Description
MetaData
is designed to contain metadata (variable values and
descriptions) from a microarray experiment. It provides a convenient way to store related
metadata in a single data structure (object). It also lets you manage and subset the data.
The metadata is a collection of variable names, for example related to samples or
microarray features, along with descriptions and values for the variables. A
MetaData
object stores the metadata in two dataset arrays.
Values
dataset array — A dataset array containing the measured value of each variable per sample or feature. In this dataset array, the columns correspond to variables and rows correspond to either samples or features. The number and names of the columns in this dataset array must match the number and names of the rows in the Descriptions dataset array. If this dataset array contains sample metadata, then the number and names of the rows (samples) must match the number and names of the columns in theDataMatrix
objects in the sameExpressionSet
object. If this dataset array contains feature metadata, then the number and names of the rows (features) must match the number and names of the rows in theDataMatrix
objects in the sameExpressionSet
object.Descriptions
dataset array — A dataset array containing a list of the variable names and their descriptions. In this dataset array, each row corresponds to a variable. The row names are the variable names, and a column, namedVariableDescription
, contains a description of the variable. The number and names of the rows in theDescriptions
dataset array must match the number and names of the columns in theValues
dataset array.
The MetaData
object includes properties and methods that let you
access, retrieve, and change metadata variables, and their values and descriptions. These
properties and methods are useful to view and analyze the metadata.
Creation
Syntax
Description
creates a MDobj
= bioma.data.MetaData(VarValues
)MetaData
object from one dataset array whose rows
correspond to sample (observation) names and whose columns correspond to variables. The
dataset array contains the measured value of each variable per sample.
creates a MDobj
= bioma.data.MetaData(VarValues
,VarDescriptions
)MetaData
object from two dataset arrays. Here,
VarDescriptions
is a dataset array whose rows correspond to
variables. The row names are the variable names, and another column, named
VariableDescription
, contains a description of each
variable.
creates a MDobj
= bioma.data.MetaData('File',FileValue
)MetaData
object from a text file containing a table of
metadata. The table row labels must be sample names, and its column headers must be
variable names.
creates a MDobj
= bioma.data.MetaData('File',FileValue
,Name,Value
)MetaData
object from a text file according to the
Name,Value
arguments.
specifies a name for the MDobj
= bioma.data.MetaData(___,'Name',NameValue
)MetaData
object. Use this syntax with any
input arguments from previous syntaxes.
Input Arguments
Properties
Object Functions
combine | Combine two MetaData objects |
isempty | Determine whether MetaData object is empty |
sampleNames | Retrieve or set sample names in MetaData object |
size | Return size of MetaData object |
varValuesTable | Create 2-D graphic table GUI of variable values in MetaData object |
variableDesc | Retrieve or set variable descriptions for samples in MetaData object |
variableNames | Retrieve or set variable names for samples in MetaData
object |
variableValues | Retrieve or set variable values for samples in MetaData object |
Examples
Limitations
MetaData
objects support 2-D parenthesis ( )
indexing and dot .
indexing to extract, assign, and delete data.
MetaData
objects do not support:
Curly brace
{ }
indexingLinear indexing
Algorithms
An ExpressionSet
object contains two MetaData
objects, one for sample information and one for microarray feature information. A
MetaData
object contains two dataset arrays. One dataset array contains
the measured value of each variable per sample or feature. The other dataset array contains a
list of the variable names and their descriptions.
Version History
Introduced in R2009b