3.5. SesamX functions and keywords description

This part of the user manual describes each function available in SesamX. Before diving into the details, it is important to provide the relevant general information about functions, branches and keywords behaviors in the SesamX input file.

As a user you must be aware of the behavior regarding the SesamX functions:

• a function can be mandatory: if it is not present in the input file, SesamX will return an error.
• even if a function is not mandatory (i.e. optional) and not explicitly used, SesamX can automatically consider this function filled with default preset values.
• some functions cannot be used more than once in an input file. These functions are qualified as unique.

And the same behaviors apply to branches.

For instance, the CVG-CRITERIA branch of the SOLVE-NON-LINEAR-STATIC function is unique, optional and carries default preset values. We cannot call it more than once under a SOLVE-NON-LINEAR-STATIC function. If we do not call it, SesamX will consider the branch filled with default values. Of course, if there is no SOLVE-NON-LINEAR-STATIC call in the input file, the CVG-CRITERIA branch will not be considered by SesamX.

Similarly, keywords are qualified internally by attributes allowing a more efficient data description and input error management. As a user you cannot control the keywords attributes, but you must be aware of what they mean. There are 6 keyword attributes:

• the type attribute,
• the data values attribute,
• the data number attribute,
• the optional attribute,
• the default value attribute,
• the physical quantity attribute.

The type attribute informs about the type of the data held by the keyword. It can be either:

• an integer (for instance 18),
• a float (for instance 5.33),
• a string (for instance SOL_01),
• a path (for instance “..\output_folder”),
• a formula (for instance “x^2 + *y^2 + 2*z^2”),
• a boolean (YES or NO),
• an enumeration (for instance QD4).

Please note that the path and formula types are different from the string type. In SesamX, a path or formula value must always be surrounded with double quotes (i.e. “”).

The enumeration type indicates that the keyword value must be among predefined ones. And these predefined values are given by the data values attribute.

The data number attribute tells how many elementary data are expected. For instance to provide the values for a force vector, 3 float values are expected.

The optional attribute works in pair with the default value attribute. The optional attribute can be either true or false. If false, the keyword is mandatory, if true the behavior is the following :

• if the keyword is not provided by the user and its default value attribute is not empty, then SesamX will automatically assign the value provided by the default value attribute to the keyword.
• if the keyword is not provided by the user and its default value attribute is empty, SesamX will not consider the keyword.

Finally, the physical quantity attribute gives the physical quantity that will be used by SesamX to understand the numeric data. This attribute makes sense only for float values. Please refer to the units management page for more details.

The explanations provided above may seem a bit too theoretical or cumbersome. However you should not worry too much about it. In practice this mechanism is seamless and efficient. When in doubt about a function branch or keyword, you can check the related documentation. It describes concretely the behavior of SesamX.

Besides, for a given function or branch, keywords are always represented in a table format showcasing all their attributes plus a description. For instance:

• SesamX input file
• SesamX SET-UNITS function

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