Plot

constructors/destructors
    Plot()
    Plot(Library *lib)
    Plot(const Plot& o);
    ~Plot ();

methods
    const char *name() const;
    void name(const char *val);

    const char *path() const;
    void path(const char *val);

    const char *label() const;
    void label(const char *val);

    const char *desc() const;
    void desc(const char *val);

    const char *hints() const;
    void hints(const char *val);

    const char *color() const;
    void color(const char *val);

    const void *property (const char *key) const;
    void property (const char *key, const void *val, size_t nbytes);

    const char *propstr (const char *key) const;
    void propstr (const char *key, const char *val);

    void propremove (const char *key);

    Plot& add ( size_t nPts, double *x, double *y,
                const char *fmt, const char *name);

    Plot& add (Curve *c, const char *name);

    size_t count() const;

    Curve *curve (const char* name) const;
    Curve *getNthCurve(size_t n) const;

    void vvalue(void *storage, size_t numHints, va_list arg) const;
    void random();
    Rp_Chain *diff(const Object& o);

    void configure(size_t as, ClientData c);
    void dump(size_t as, ClientData c);

    Outcome &outcome() const;

    const int is() const;

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const char *name()
    Purpose: get the id name of the object
    Input Arguments: None
    Return Value: the id name stored in the object.
    Notes: if no name is set, NULL will be returned
            the id name is used to identify this object from
            all other objects and should be unique
    Code Example:

void name(const char *val)
    Purpose: set the id name of the object
    Input Arguments: 1
        1. const char *val - new id name
    Return Value: None
    Notes: a copy of the memory location val will be stored
    Code Example:

const char *path()
    Purpose: get the path of the object
    Input Arguments: None
    Return Value: the path stored in the object.
    Notes: if no path is set, NULL will be returned
            the path tells where this object sits in the
            hierarchy of objects.
    Code Example:

void path(const char *val)
    Purpose: set the path of the object
    Input Arguments: 1
        1. const char *val - new path
    Return Value: None
    Notes: a copy of the memory location val will be stored
    Code Example:

const char *label()
    Purpose: get the label of the object
    Input Arguments: None
    Return Value: the label stored in the object.
    Notes: if no label is set, NULL will be returned
            the label is used by the graphical user interface.
    Code Example:

void label(const char *val)
    Purpose: set the label of the object
    Input Arguments: 1
        1. const char *val - new label
    Return Value: None
    Notes: a copy of the memory location val will be stored
    Code Example:

const char *desc()
    Purpose: get the description of the object
    Input Arguments: None
    Return Value: the description stored in the object.
    Notes: if no description is set, NULL will be returned
            the description is used by the graphical user
            interface to describe what type of data is being
            requested and how the input is used.
    Code Example:

void desc(const char *val)
    Purpose: set the description of the object
    Input Arguments: 1
        1. const char *val - new description
    Return Value: None
    Notes: a copy of the memory location val will be stored
    Code Example:

const char *hints()
    Purpose: get the hints of the object
    Input Arguments: None
    Return Value: the hints stored in the object.
    Notes: if no hints are set, NULL will be returned
            the hints are used by the graphical user interface
    Code Example:

void hints(const char *val)
    Purpose: set the hints of the object
    Input Arguments: 1
        1. const char *val - new hints
    Return Value: None
    Notes: a copy of the memory location val will be stored
    Code Example:

const void *property (const char *key) const;
    Purpose: get a generic property from the property database
    Input Arguments: 1
        1. const char *key - property name
    Return Value: value of the property
    Notes: None
    Code Example:

void property (const char *key, const void *val, size_t nbytes);
    Purpose: set a generic property in the property database
    Input Arguments: 3
        1. const char *key - property name
        2. const void *val - property value
        3. size_t nbytes - size (in bytes) of the value
    Return Value: None
    Notes: A copy of the memory pointed to by val is stored
            in the property database
    Code Example:

const char *propstr (const char *key) const;
    Purpose: get a string property from the property database
    Input Arguments: 1
        1. const char *key - property name
    Return Value: value of the property
    Notes: None
    Code Example:

void propstr (const char *key, const char *val);
    Purpose: set a string property in the property database
    Input Arguments: 2
        1. const char *key - property name
        2. const char *val - property value
    Return Value: None
    Notes: A copy of the memory pointed to by val is stored
            in the property database
    Code Example:

void propremove (const char *key);
    Purpose: remove a property from the property database
    Input Arguments: 1
        1. const char *key - property name
    Return Value: value of the property
    Notes: None
    Code Example:

Plot& add (size_t nPts, double *x, double *y,
           const char *fmt, const char *name);
    Purpose: add data for an xy curve to the plot
    Input Arguments: 5
        1. size_t nPts - number of points in the x and y arrays
        2. double *x - pointer to array representing the x axis
        3. double *y - pointer to array representing the y axis
        4. const char *fmt - format of the line
        5. const char *name - id of the newly created curve
    Return Value: reference to a Plot object
    Notes: format can be something like "g:o" to represent
            green line, dotted line style, circle marker.
            this follows matlab's formatting rules.
    Code Example:

Plot& add (Curve *c, const char *name);
    Purpose: add a Curve object to this Plot object
    Input Arguments: 2
        1. Curve *c - Curve object to add
        2. const char *name - id of the Curve object
    Return Value: reference to a Plot object
    Notes: Curve object should not be deleted by user?
    Code Example:

size_t count() const;
    Purpose: retrieve the number of curves in this Plot object
    Input Arguments: 0
    Return Value: number of curves stored in the object
    Notes: None
    Code Example:

Curve *curve (const char* name) const;
    Purpose: retrieve the curve with the id matching "name"
    Input Arguments: 1
        1. const char *name - id to Curve to be retrieved
    Return Value: pointer to Curve object matching "name" or NULL
    Notes: None
    Code Example:

Curve *getNthCurve(size_t n) const;
    Purpose: return the n'th curve stored in the object
    Input Arguments: 1
        1. size_t n - number of the curve to retrieve
    Return Value: pointer to the n'th Curve object stored in
                    the Plot object or NULL
    Notes: None
    Code Example:

void vvalue(void *storage, size_t numHints, va_list arg) const;
    Purpose: return the value of the object after applying a
                varying number of hints about how the value
                should be configured
    Input Arguments: 3
        1. void *storage - the return value
        2. size_t numHints - number of hints provided
        3. va_list arg - list of hints specified as a va_list
    Return Value: None
    Notes: vvalue will parse out the recognisable hints from
                va_list arg. Values stored in the object are
                not changed.
    Code Example:

void random();
    Purpose: populate the object with a random value
    Input Arguments: 0
    Return Value: None
    Notes: the current value of this object will be populated
           with a random value that fits within the min and
           max if they were specified.
    Code Example:

Rp_Chain *diff(const Rp_Object &o);
    Purpose: return a linked list showing the differences between
             this object and Rp_Object &o
    Input Arguments: 1
        1. const Rp_Object &o - object to diff against
    Return Value: list of differences between objects
    Notes: None
    Code Example:

void configure(size_t as, ClientData c);
    Purpose: configure the object based on the data in "c".
                use "as" to determine the type of data in "c".
    Input Arguments: 2
        1. size_t as - type of data stored in "c".
                        valid values include:
                            RPCONFIG_XML
                            RPCONFIG_TREE
        2. ClientData c - data to configure the object from.
                            if as is...     then c should be...
                            RPCONFIG_XML    const char *xmltext
                            RPCONFIG_TREE   RP_ParserXML *object
    Return Value: None
    Notes: object is configured based on values in "c"
    Code Example:

void dump(size_t as, ClientData c);
    Purpose: dump the object values based to the object "c".
                use "as" to determine how to dump the data.
    Input Arguments: 2
        1. size_t as - type of data stored in "c".
                        valid values include:
                            RPCONFIG_XML
                            RPCONFIG_TREE
        2. ClientData c - data to configure the object from.
                            if as is...     then c should be...
                            RPCONFIG_XML    ClientDataXml *object
                            RPCONFIG_TREE   RP_ParserXML *object
    Return Value: None
    Notes: None
    Code Example:

Outcome &outcome() const;
    Purpose: return the status of this object as an Outcome.
    Input Arguments: 0
    Return Value: status of the object as an Outcome
    Notes: None
    Code Example:

const int is() const;
    Purpose: return an integer tag describing the object.
    Input Arguments: 0
    Return Value: integer tag unique to all plot objects
    Notes: None
    Code Example:
