SFA Project On-line Documentation: DataSet

here is a diagram that shows how to visualize the data structure:

//
//  DataSet.H  
//
//  This file defines the main DataSet class that describes a single entry
//  in our top level data structure.
//
//  Ted Bedwell and Jim Kukla Jan. 1998
//
//  $Id: DataSet.H,v 1.9 1998/03/30 13:47:59 jkukla1 Exp $

#ifndef SFA_DATASET_H
#define SFA_DATASET_H 1

#include "String.H"
#include "MappingNode.H"
#include "PackedGlyph.H"


class DataSetList;
class String;

class DataSet
{
private:

  //Static class variables

  static long next_id;
  static int num_maps;

  // Data Set label and unique ID
  
  long set_id;
  String set_label;
  
  //Number of Data Dimensions and their length
  
  int num_dimen;     
  int dimen_length;
  int num_tsteps;

  //  Some internal run-time state variables:  the current time step 
  //  and whether or not this data set is currently within view.
  int current_tstep;
  int visible;

  //Data Dimensions
  
  double ***dimen;
  
  //  Max and min values of each dimension
  struct Maxmin {double max, min; } *dimen_maxmin;

  //Array of Data Dimension Labels
  
  String *dimen_labels;
  
  //Display Dimension Mappings

  double **maps;  
  MappingNode ** mappings;

  //  An array of translated copies of each data dimension.
  //  These are generated on-demand for each time step when 
  //  a request to view that time step arrives.  At that point,
  //  the view is cached.  The theory is that most data sets are
  //  static and so we can avoid re-translating data dimensions
  //  quite often.  A dirty flag is associated with each data set
  //  in hopes that data sets will either be very dynamic or totally
  //  static.  If this granularity proves inadequate, future revisions
  //  may use a flag per time step.  Hopefully this will not be 
  //  needed.
  PackedGlyph ** cooked_data;
  char           cooked_data_dirty;

  //  Labels for each of the display dimensions.
  static   String display_dimension_labels[] ;

  //  A list of the currently defined mapping functions.
  static  MappingFunction mapping_function_table[];



 public:

  //Constructor
  
  DataSet(const String & label, int dimensions, int length, int tstep); 

  //Destructor

  ~DataSet();

  //Insert a data dimension
  void setDimension(int tstep, int index, double *&data, String label);
  
  //Set and Unset a dimension label
  void setDimenLabel(int index, const String & label);
  void unsetDimenLabel(int index);
  

  //  Set and Get dimension min max values
  void setDimenMaxmin(int index, double mx, double mn);
  double getDimenMax(int index);
  double getDimenMin(int index);
  

  //Set data set Label in case it needs to change
  void setSetLabel(String & label);
  
  //Set and unset a mapping
  void setMap(int map_index, int dimen_index);
  void unsetMap(int map_index);
  
  // Accessor to get the set id
  int getID() {return set_id;}

  // Accessor that returns the number of time steps in the data set
  int getTsteps() const {return num_tsteps;}

  //  Mutator that tries to set the new time step to tstep and 
  //  returns the new time step if successful, the old one if not.
  //
  //    To check for errors, use something like:  
  //  if (ts != ds.setCurrentTstep(ts)) 
  //     cerr << "Time Step unchanged.  Error.\n";
  int setCurrentTstep(int tstep);

  //  Accessor that returns the current time step in the data set
  int getCurrentTstep() const { return current_tstep; }

  // Accessor to get the set label
  String getLabel() {return set_label;}
  
  //  Method that performs the translation from raw data to the 
  //  display-ready cooked format.
  int translate(void);

  //  Method to read in a set file named filename from disk and
  //  initialize all the appropriate data members of the instance.
  int  readFile(String filename);
 
  //Print test routine
  void print() const;

  friend int main(int, char **);
};



#endif

Constructors

DataSet(const String & label, int dimensions, int length, int tstep)

Mutators

void setDimension(int tstep, int index, double *&data, String label)

void setDimenLabel(int index, const String & label)

void unsetDimenLabel(int index)

void setDimenMaxmin(int index, double mx, double mn)

Note that these are not necessarily values in the data set, but represent a theoretical min-max pair. This can be used for cases where the possible range of values is very great, but the actual values all fall within a close range. This helps avoid perceptual misunderstandings about mappings where a relatively closely grouped set of values appear as a very wide range of display values.

void setSetLabel(String & label)

void setMap(int map_index, int dimen_index)

void unsetMap(int map_index)

int setCurrentTstep(int tstep)

To check for errors, use something like:

 
  if (ts != ds.setCurrentTstep(ts)) 
       cerr << "Time Step unchanged.  Error.\n";

int translate(void)

int readFile(String filename)

Accessors

int getCurrentTstep() const

String getLabel()

double getDimenMax(int index)

There is currently no error checking for this function.

double getDimenMin(int index)

There is currently no error checking for this function.

int getID()

During a single run of SFA two data sets are guaranteed not to have the same ID.

int getTsteps() const

void print() const