1. Generalities#

1.1. What is a table?#

A table is a computer data structure that stores a set of integer, real, complex, or character string values.

A table is comparable to a database EXCEL (version 5), that is to say that it can be seen as a list of columns (the term « column » is here to make the comparison with a list EXCEL; this does not mean that a table is always printed in columns (see § 8 Printing a table)) facing each other. Each column has a field name, which we call a parameter, and contains similar data such as I, R, C, K8, K16, K16, K24, or K32.

Example 1: T1

Example 2: T2

ACTION

NUME_ORDRE

INST

NOEUD

DX

DY

MAILLE

SIXX

INTITULE 1

1

N1

INTITULE 1

1

N2

INTITULE 1

1

N3

INTITULE 1

2

N1

INTITULE 1

2

N2

INTITULE 1

2

N3

INTITULE 2

2

MA1

-12.

INTITULE 2

2

MA2

-14.

1.2. Some properties of tables#

  • A table has a limited number of columns (or parameters). These parameters are chosen by the developers of the commands that create tables. The name of a parameter is a string that is up to 16 characters in length.

  • On the other hand, the number of rows in a table is often « dynamic »: it generally depends on the user’s choices: counting nodes, calculation times,…

  • The values contained in a column of a table are all of the same type FORTRAN: real, complex, integer or text. SD Aster names or JEVEUX object names can be stored in « text » form in a table; for example function names.

  • A table is said to be « full » when all its rows contain values for all the parameters in the table. Table t1 above is full. A table that is not full is said to be « hollow » (table t 2 above).

  • The rows in a table are naturally ordered by the order in which they were inserted into the table (routine TBAJLI).

  • The columns of a table are naturally ordered by the order in which their parameters are declared (routine TBAJPA).

  • A table has at least one row. On a line, there may be empty cells: the associated parameter is not affected (table t2 above).