/PARAMETER

Block Format Keyword This card defines values of parameters in the Starter file that will be used throughout the Radioss model.

The values replace the corresponding parameter names in various Radioss cards. The option allows easier parameterization of the model.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
/PARAMETER/range/type/Parameter_ID
parameter_title
If type = INTEGER
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
ParName Ivalue
If type = REAL
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
ParName Rvalue
If type = INT_EXPR or REAL_EXPR
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
ParName Expression
... Expression ...
Up to 10 lines
If type = TEXT
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
ParName Length
Text
Up to 10 lines

Definition

Field Contents SI Unit Example
range
GLOBAL
Parameter value is used everywhere in the input deck.
LOCAL
Parameter value is used only inside of a certain submodel. Note that GLOBAL parameter definition with same parameter name will be overwritten.
type Parameter type:
INTEGER
Integer value
REAL
Real value
INT_EXPR
Equation of integer parameters
REAL_EXPR
Equation of real parameters
TEXT
Text characters
Parameter_ID Parameter identifier.

(Integer, maximum 10 digits)

parameter_title Parameter title.

(Character, maximum 100 characters)

ParName Parameter name. 3

(Character string, maximum of 9 characters and MUST be aligned to the left of the field for all types, except type=TEXT)

Ivalue Parameter integer value.

(Integer, maximum 10 digits)

Rvalue Parameter real value.

(Real, maximum 20 digits)

Expression Parameter expression. 6
Length Length of character parameter.
= 0
The full line is read.

(Integer, maximum 100 digits)

Text Parameter character text.

(Character string, maximum of 100 characters)

Example 1

Example 2

Example 3

Example 4

Example 5

Example 6

Comments

  1. /PARAMETER/LOCAL cards can be specified and used only inside of a submodel (//SUBMODEL). Local parameter overwrites a global parameter definition with the same name inside of the submodel, where it is specified. Local parameters can be specified in any part of submodel.
  2. ParName requirements:
    • Only letters, numbers, and underscores are valid characters; no other characters are allowed.
    • Parameter names must always begin with a letter and are case sensitive; for example, Thickness, THICKNESS, and thickness are all different variable names.
    • Parameter names cannot be words reserved for Templex statements, implicit variables, or string and mathematical functions or operators defined in the Math Reference section of the API, Reference Guide. These reserved words are not case sensitive; for example, Time, time, TIME, Date, date, DATE are not valid parameter names because Time and Date are math functions.
    • Names of include files, and keywords cannot be used as parameters.
  3. Parameters with a name ParName can be referenced after /BEGIN card for global parameters and in any place of submodel for local parameters, using the syntax, &ParName. Multiple references of such parameters are possible.
  4. The &ParName input found after /BEGIN is replaced by the corresponding parameter value or keyword identifier starting at the location of the & in the variable name extending 10 digits for an integer, 20 digits for a real value, and Length input value for type=TEXT.

    The character '&' can be used in the model only for referring parameters or keyword identifiers. It should not be used in card titles that are not defined as parameters.

    In Example 1, a parameter named "TTF" is defined in the /PARAMETER card. The value of the parameter (10) is aligned to the left of the field. The parameter is used with an additional prefix "&", in the /SENSOR card.

  5. If the minus (-) sign is used before the prefix "&", as:

    -&ParName

    Then, the value of the parameter is multiplied by -1. In this case, ParName must not exceed 8 digits.

    For example (Example 2), if you need exchange external surface normal for airbag.
    • Set parameter s_part=4 and specific -&s_part in surface definition, then a value of "-4" will be substituted for -&s_part. -> shell normal reversed.
    • Set parameter s_part=-4 and specific &s_part in surface definition, then a value of "-4" will be substituted for &s_part. -> shell normal reversed.
    • Set parameter s_part=-4 and specific -&s_part in surface definition, then a value of "4" will be substituted for -&s_part". -> shell normal not reversed.
  6. The expression parameter cards, type /INT_EXPR or /REAL_EXPR accept parameters as arguments. These argument parameters should be defined before these expression parameter cards in the input deck. The expression results are calculated to a maximum accuracy of 12 digits. The external templex program is used to evaluate expressions. Refer to Expression Operators for more information.

    In Example 3, parameters MW and CPM are defined before the expression parameter card type /REAL_EXPR. The expression parameter card (/4) calculates the value of CP which is equal to CPM/MW. The value MW1 cannot be used in this expression parameter card (/4) because it is defined after the /REAL_EXPR card. If CPM/MW1 is specified in the expression parameter card (/4), the program runs into an error.

  7. During the execution of the expression parameter types INT_EXPR or REAL_EXPR, Radioss Starter calls an external executable: templex. This program is available in the standard Altair HyperWorks installation. The call to templex.exe is automatically managed by the Compute Console (ACC) or the Radioss run script. Refer to Run Radioss.
  8. If the Compute Console (ACC) or the Radioss run script is not used, the following environment variables need to be defined:
    • TEMPLEX_PATH

      Windows: =%ALTAIR_HOME%\hw\bin\[win64]\

      Linux: $ALTAIR_HOME/hw/bin/linux64/

    • On Linux, update LD_LIBRARY_PATH with the following path: $ALTAIR_HOME/hw/tcl/tcl[version]/linux64/lib;$ALTAIR_HOME/hw/bin/linux64; $ALTAIR_HOME/hw/lib/linux64
      Note: The fields within [ ] will need to be updated with the correct values.
  9. Type could also be TEXT.

    In Example 4, the string " 1 1 0" is defined for TEXT parameter "var". This parameter is used in part definition. The property ID 1 and material ID 1 have been set for part 5.

  10. TEXT type parameter can be used to specify the direction for an imposed movement. Since the text input to /IMPDISP must be right justified, the &RotX must be right justified when entered. Since &RotX is 5 characters long, Length=5 and the text must be entered as 5 characters right justified, “ XX”: See Example 5.
  11. TEXT type parameter can be stitched together with character “$”: See Example 6.