|  | ## Read Sparse

#### Synopsis

Reads an example file in sparse format.

#### Description

Reads an example file in sparse format, i.e. lines have the form

label index:value index:value index:value...

Index may be an integer (starting with 1) for the regular attributes or one of the prefixes specified by the parameter list `prefix_map`. Four possible `format`s are supported

format_xy
  The label is the last token in each line
format_yx
  The label is the first token in each line
format_prefix
  The label is prefixed by 'l:'
format_separate_file
  The label is read from a separate file specified by `label_file`
no_label
  The example set is unlabeled.

A detailed introduction to the sparse file format is given in section First steps/File formats/Data files.

#### Input

#### Output

- output:

#### Parameters

- format: Format of the sparse data file.
- attribute description file: Name of the attribute description file.
- data file: Name of the data file. Only necessary if not specified in the attribute description file.
- label file: Name of the data file containing the labels. Only necessary if format is 'format_separate_file'.
- dimension: Dimension of the example space. Only necessary if parameter 'attribute_description_file' is not set.
- sample size: The maximum number of examples to read from the data files (-1 = all)
- use quotes: Indicates if quotes should be regarded.
- quotes character: The quotes character.
- datamanagement: Determines, how the data is represented internally.
- decimal point character: Character that is used as decimal point.
- prefix map: Maps prefixes to names of special attributes.
- encoding: The encoding used for reading or writing files.

#### ExampleProcess

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