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Input Rules

The input files of FrontISTR (overall control data .dat, analysis control data .cnt, mesh data .msh) follow common notation rules.

File Characteristics

  • Free-format ASCII files.
  • Composed of headers starting with ! followed by their associated data.
  • The order of headers is basically arbitrary.
  • Data fields are separated by commas ,.

Note: Analysis control data specific

The analysis control data (.cnt) has additional characteristics:

  • The file is broadly divided into three zones: calculation control data, solver control data, and post-processing (visualization) control data.
  • The file must end with !END.

Identifies the meaning and data block of the data. A line starting with ! is treated as a header.

Header Line

Describes the header and its associated parameters.

  • A header line must begin with the header.
  • If parameters are required, they must follow with a , separator.
  • If a parameter takes a value, = follows the parameter name, then the value.
  • A header line cannot span multiple lines.

Data Lines

Begin on the line after the header line and describe the required data.

  • Data lines may span multiple lines, as determined by the data description rules defined for each header.
  • Data lines may not be required.

Delimiter

The data delimiter is a comma ,.

Whitespace

Whitespace is ignored.

Names

Characters allowed in names are underscore _, hyphen -, and alphanumeric characters a-z A-Z 0-9. The first character must be _ or an alphabetic character a-z A-Z.

  • Case is not distinguished; internally all characters are treated as uppercase.
  • The maximum length of a name is 63 characters.

File Names

Characters allowed in file names are underscore _, hyphen -, period ., slash /, and alphanumeric characters a-z A-Z 0-9.

  • File names may include paths unless otherwise noted. Both relative and absolute paths are accepted.
  • The maximum length of a file name is 1023 characters.

Floating Point Data

An exponent is optional. If present, it must be preceded by E or e. Either E or e may be used.

Note:

D or d cannot be used as the exponent designator.

Comment Lines

Lines starting with !! or # are treated as comment lines and ignored.

  • Comment lines may be inserted at any position in the file, with no limit on their number.

!END

Indicates the end of data. When this header appears, reading of the data terminates.