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: http://xmm.vilspa.esa.es/sas/5.4.1/doc/deceit/node3.html
Дата изменения: Fri Jan 10 22:43:01 2003 Дата индексирования: Sat Dec 22 07:37:24 2007 Кодировка: Поисковые слова: quasar |
With deceit it is possible to create datasets (e.g., FITS files) without the need to do any complex programming. Within the constraints of the DAL data model, datasets of any complexity can be created. The datasets are described with a high level specification which may be thought of as a template. All the features of the DAL data model are supported. The template approach has the added advantage of documenting the dataset structure.
Throughout this document it is assumed that the reader has a basic understanding of the DAL data model.
By default, deceit creates the dataset empty; that is to say, the attributes are filled in as specified in the template, but none of the data structures are filled in with data.
Optionally, certain functions may be called from within the template. These functions allow one to use data contained in ASCII files to populate the arrays and columns of a dataset. It is possible for users to write their own Perl functions which may then be called from within a template. A number of Perl functions are provided that make use of the pedal, the Perl interface to the dal.
deceit cannot be used to modify an existing dataset.