[ library(vc_support) | The ECLiPSe Libraries | Reference Manual | Alphabetic Index ]

# viewable_element(++ViewableName, ++IndexList, ?ViewableElement)

Index a viewable element inside a viewable.

ViewableName
  Atom: name of an existent viewable.
IndexList
  List of integers: the coordinates of the viewable element within the viewable.
ViewableElement
  Term to be unified with the viewable element.

## Description

Note that this predicate throws an error if there are no current visualisation clients. Retrieves a single viewable element from a named viewable, given the element's array coordinates, and unifies it with ViewableElement. IndexList must be a ground list which has one positive integer for each dimension of the viewable.

### Fail Conditions

ViewableName is not instantiated to the name of an existent viewable. ViewableElement will not unify with the specified element.

### Resatisfiable

no

### Exceptions

(1) general error
  There are no current visualisation clients
(4) instantiation fault
  ViewableName is not an atom or string
(5) type error
  IndexList is not a ground list of integers
(6) out of range
  A co-ordinate in Index is out of range
(8) bad argument list
  IndexList has the wrong number of elements

## Examples

           Success:

           Failure:

           Exceptions raised:

## See Also

viewable : viewable_create / 3, viewable : viewable_size / 2, viewable_element_to_string / 2, viewable_element_execute / 3