TrajectoryReader module¶

Module contents¶

template<typename TrajectoryT> class TrajectoryReader : public tracktable::GenericReader<TrajectoryT>¶

Read trajectories from files.

This reader wraps the following pipeline:

Read lines from a text file
Skip any lines that begin with a designated comment character (‘#’ by default)
Tokenize each line using specified delimiters (whitespace by default)
Create a trajectory (user-specified type) from each tokenized line
Return the resulting points via a C++ iterator

You will use set_input() to supply an input stream, set_comment_character() to configure which lines to skip, set_field_delimiter() to specify how to turn lines into fields.

Public Functions

inline TrajectoryReader()¶

Instantiate TrajectoryReader using a default configuration.

Default reader configuration.

If you are reading BasePoints, this sets coordinates 0 to d-1 (D is the point’s dimension) using columns 0 to d-1.

If you are reading TrajectoryPoints, column 0 is the object ID, column 1 is the timestamp, and columns 2 through D+1 (inclusive) are the coordinates.

These are the default settings. You can override any or all of them after you instantiate the reader.

inline TrajectoryReader(std::istream &infile)¶

Instantiate a TrajectoryReader using a std::istream and default configuration.

Default reader configuration.

If you are reading BasePoints, this sets coordinates 0 to d-1 (D is the point’s dimension) using columns 0 to d-1.

If you are reading TrajectoryPoints, column 0 is the object ID, column 1 is the timestamp, and columns 2 through D+1 (inclusive) are the coordinates.

These are the default settings. You can override any or all of them after you instantiate the reader.

Parameters:: infile – [in] Stream to read input from

inline TrajectoryReader(TrajectoryReader const &other)¶

Copy contructor, create a reader with a copy of another.

Parameters:: other – [in] TrajectoryReader to copy from

inline virtual ~TrajectoryReader()¶: Destructor.

inline TrajectoryReader &operator=(TrajectoryReader const &other)¶

Assign a TrajectoryReader to the value of another.

Parameters:: other – [in] TrajectoryReader to assign value of
Returns:: Reader with the new assigned value

inline bool operator==(TrajectoryReader const &other) const¶

Check whether one reader is equal to another by comparing all the properties.

Two readers are equal if all of their properties are equal.

Parameters:: other – [in] TrajectoryReader for comparison
Returns:: Boolean indicating equivalency

inline bool operator!=(TrajectoryReader const &other) const¶

Check whether two TrajectoryReaders are unequal.

Parameters:: other – [in] TrajectoryReader for comparison
Returns:: Boolean indicating equivalency

inline void set_default_configuration()¶

Default reader configuration.

If you are reading BasePoints, this sets coordinates 0 to d-1 (D is the point’s dimension) using columns 0 to d-1.

If you are reading TrajectoryPoints, column 0 is the object ID, column 1 is the timestamp, and columns 2 through D+1 (inclusive) are the coordinates.

These are the default settings. You can override any or all of them after you instantiate the reader.

inline void set_comment_character(string_type const &comment)¶

Specify comment character for skipping lines.

A line is a comment if and only if its first non-whitespace character is the comment character (‘#’ by default). We will skip such lines entirely. We do not handle inline or trailing comments: a line will either be included in its entirety or skipped completely.

Parameters:: comment – [in] Single character

inline string_type comment_character() const¶

Retrieve current value of comment character.

This function invalidates any outstanding iterators.

Returns:: Current value of comment character

inline void set_null_value(string_type const &_null_value)¶

Specify string value to be interpreted as null.

Parameters:: _null_value – [in] String to interpret as null

inline string_type null_value() const¶

Get string value for nulls.

Returns:: Current string that will be interpreted as null

inline void set_input(std::istream &_input)¶

Supply input stream from delimited text source.

We read our input from C++ std::istreams. The stream you supply will be traversed exactly once.

Parameters:: _input – [in] Stream from which we will read points

inline std::istream &input() const¶

Retrieve the current input stream.

Bug:: We currently have no way to indicate whether the stream is valid.

Returns:: Stream being used for input.

inline void set_warnings_enabled(bool onoff)¶

Enable/disable warnings during parsing.

We may run into type mismatches and bad casts while we’re parsing headers and data. This flag determines whether or not warnings will be printed.

Parameters:: onoff – [in] Warnings are on / off

inline bool warnings_enabled() const¶

Check whether warnings are enable.

Returns:: Whether or not warnings are on

inline void set_field_delimiter(string_type const &delimiters)¶

Set one or more characters as field delimiters.

Each character in the argument to this function will be treated as a potential field delimiter. If you supply ",|" as your delimiter then both the comma and the exclamation point will be used to tokenize field.

This function invalidates any outstanding iterators.

Parameters:: delimiters – [in] String containing all desired delimiter characters

inline string_type field_delimiter() const¶

Retrieve the current set of delimiter characters.

Returns:: String containing all delimiters

inline void set_timestamp_format(string_type const &format)¶

Set the format of the timestamp.

Parameters:: format – [in] String containing the format of the time stamp

inline string_type timestamp_format() const¶

Retrieve the format of the timestamp.

Returns:: The timestamp format

Private Types

typedef TrajectoryT trajectory_type¶

typedef trajectory_type::point_type point_type¶

typedef tracktable::LineReader line_reader_type¶

typedef tracktable::SkipCommentsReader<line_reader_type::iterator> skip_comments_reader_type¶

typedef tracktable::StringTokenizingReader<skip_comments_reader_type::iterator> string_tokenizer_type¶

typedef boost::shared_ptr<trajectory_type> trajectory_shared_ptr_type¶

typedef string_vector_type::const_iterator token_iter_type¶

typedef std::pair<token_iter_type, token_iter_type> token_range_type¶

typedef std::vector<token_range_type> token_range_vector_type¶

typedef PointFromTokensReader<point_type, token_range_vector_type::iterator> point_reader_type¶

Private Functions

inline virtual trajectory_shared_ptr_type next_item()¶

Increment the iterator the next item to be read in.

Returns:: The next item

inline trajectory_shared_ptr_type parse_trajectory(string_vector_type const &tokens)¶

Parse the read in trajectory.

Parameters:: tokens – Tokens that are read in and parsed

inline void populate_trajectory_points(token_iter_type token_begin, token_iter_type token_end, std::size_t num_points, trajectory_shared_ptr_type trajectory)¶

Populate the trajectorie’s points.

Parameters:

token_begin – [in] Start of tokens read in
token_end – [in] End of tokens read in
num_points – [in] Num of points expected to be in trajectory
trajectory – [in] Trajectory to populate

inline void populate_trajectory_points_from_token_ranges(token_range_vector_type::iterator input_range_begin, token_range_vector_type::iterator input_range_end, trajectory_shared_ptr_type trajectory)¶