Operator DEFI_FONCTION

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Titrate:

Operator

DEFI_FONCTION

Date:

02/03/06

Author (S):

COURTEOUS Mr.

Key

U4.31.02-I1

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Instruction manual

U4.3- booklet: Function

HT-62/06/004/A

Organization (S):

EDF-R & D/AMA

Instruction manual
U4.3- booklet: Function
Document: U4.31.02

Operator

DEFI_FONCTION

1 Goal

To define a real or complex function of a real variable. This operator allows to define, by
example, of the characteristics materials function of the temperature, or the boundary conditions which
depend on a variable of space or time.

The concept produced by this operator is of type

function

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Operator

DEFI_FONCTION

Date:

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Key

U4.31.02-I1

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2 Syntax

F [function] =

DEFI_FONCTION

(

NOM_PARA

= Np,

NOM_RESU

=/“TOUTRESU”,

[DEFECT]

NR,

[K8]

VALE

lv,

[l_R]

VALE_C

lv,

[l_C]

VALE_PARA

[listr8]

VALE_FONC = lo, [listr8]

NOEUD_PARA

lno, [l_noeud]

MESH

my,

[mesh]

VALE_Y = ly,

[l_R]

PROL_DROITE =/“CONSTANT”,

/“LINEAR”,

/“EXCLUDED”, [DEFECT]

PROL_GAUCHE =

/“CONSTANT”,

/“LINEAR”,

/“EXCLUDED”,

[DEFECT]

Interpol

“FLAX”,

[DEFECT]

“LOG”,

“NOT”,

INFORMATION

[DEFECT]

/2,

VERIF =

“GROWING”,

[DEFECT]

“NOT”,

TITRATE =

Ti, [l_Kn]

)

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Operator

DEFI_FONCTION

Date:

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Key

U4.31.02-I1

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U4.3- booklet: Function

HT-62/06/004/A

3 Operands

3.1 Operand

NOM_PARA

NOM_PARA = Np

Indicate the name of the parameter (variable or X-coordinate) of the function.
Possible values for

are:

“TEMP”

“INST”

“EPSI”

“SIGM” “META”

“X”

“Y”

“Z”

“FREQ”

“SWEATERS”

“AMOR”

“ABSC” “DSP”

“DX”

“DY”

“DZ”

“DRX”

“DRY”

“DRZ”

“HYDR”

“SECH”

“PORO”

“SAT” “PGAZ”

“PCAP”

“QUICKLY” “ENDO”

“NORM”

This list is not exhaustive, the user can choose the name of its parameter (cf notices
in NOM_RESU).

3.2 Operand

NOM_RESU

NOM_RESU = NR

Indicate the name of the result (8 characters). The function thus created is NR = F (Np).

Note:

Certain controls (CALC_FONCTION, DEFI_MATERIAU…) check coherence

names of the parameter and result according to their context. For example, one
a traction diagram defined by a function waits of which NOM_PARA=' EPSI' and
NOM_RESU=' SIGM'.

3.3 Operand

VALE

/VALE = lv

is the list of values

, y

,…, X

, y

)

with in the order:

, y

(the first value of the parameter and the corresponding value of the result),

…

, y

(the last value of the parameter and the corresponding value of the result).

Note:

The list

values must be described in the order of the X-coordinates (X) increasing.

3.4 Operand

VALE_C

/VALE_C = lv

is the list of the values

(X, y, Z,…, X

, y

, Z

)

with:

values of the parameter

…

, Z

the real part and the imaginary part of the function complex for it

parameter.

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Operator

DEFI_FONCTION

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HT-62/06/004/A

3.5 Operand

VALE_PARA

/VALE_PARA =

is the list of the values of the parameter

(X-coordinates): it is a concept of the type

listr8

created previously by the control

DEFI_LIST_REEL

[U4.34.01].

3.6 Operand

VALE_FONC

/VALE_FONC = lo

is the list of the values of the parameter

(ordinates): it is a concept of the type

listr8

created previously by the control

DEFI_LIST_REEL

[U4.34.01].

VALE_PARA and VALE_FONC must be identical cardinals if not the control stops

in error.

3.7 Operand

NOEUD_PARA

/NOEUD_PARA = lno

lno

list nodes allowing to define the values of the X-coordinates of the function to be defined.

The X-coordinates will be equal to the curvilinear X-coordinates of the nodes on the curve that they
define.

3.8 Operands

PROL_DROITE

and

PROL_GAUCHE

PROL_DROITE

and

PROL_GAUCHE =

Define the type of prolongation on the right (on the left) of the field of definition of the variable:

“CONSTANT” for a prolongation with the last (or first) value of

function,

“LINEAR” for a prolongation along the first definite segment

(

PROL_GAUCHE)

or of the last definite segment (

PROL_DROITE

“EXCLUDED”

if the extrapolation of the values apart from the field of definition of
parameter is prohibited (in this case if a calculation requires a value
function out of the field of definition, the code will stop in
fatal error).

For example:

PROL_DROITE = “CONSTANT”, PROL_GAUCHE = “CONSTANT”

n-1

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PROL_DROITE = “LINEAR”, PROL_GAUCHE = “EXCLUDED”

n-1

Note:

The type of prolongation and interpolation are independent one of the other.

3.9 Operand

Interpol

Interpol

Type of interpolation of the function enters the values of the field of definition of the function: one
type for the interpolation of the parameter and for the interpolation of the function. This is obtained in
providing a list of texts among:

Interpol

(“FLAX”,

“LOG”)

“FLAX”

linear,

“LOG”

logarithmic curve,

“NOT”

one does not interpolate (and thus the program will stop if for the value is asked

function for a value of the parameter where it was not defined).

Note:

If only one value is specified, it is taken into account at the same time by the interpolation of
parameter and of the function.

INTERPOL = “LOG”

is equivalent to (

“LOG”, “LOG”)

3.10 Operand

INFORMATION

INFORMATION

Specify the options of impression on the file

MESSAGE

no the impression (default option)

impression of the parameters plus the list of the first 10 values in the ascending order
parameter

3.11 Operand

VERIF

VERIF

The operator

DEFI_FONCTION

check that the values of the X-coordinates are strictly increasing.

If it is not the case, an error is started. This is the behavior by defect,

VERIF

is worth

“GROWING”

The user with the possibility of not making this checking while indicating

VERIF=' NON'

. In it

case, one does not start an error and the function is reordered by increasing X-coordinates.

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Operator

DEFI_FONCTION

Date:

02/03/06

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Key

U4.31.02-I1

Page:

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Instruction manual

U4.3- booklet: Function

HT-62/06/004/A

3.12 Operand

TITRATE

TITRATE = Ti

Titrate attached to the concept produced by this operator [U4.03.01].

3.13 Operands

MESH

and VALE_Y

These two key words should be informed if one defines the function starting from NOEUD_PARA.

MESH = my

Name of the mesh associated with the list with node

lno

VALE_Y = lv

List values of the ordinates of the function to be defined.

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Operator

DEFI_FONCTION

Date:

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Key

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Instruction manual

U4.3- booklet: Function

HT-62/06/004/A

Definition of a function depending on time

4.1

Function and variables entered in the form of realities

Definition of a function (linear by pieces) depends on time (parameter

INST

- 1

EX 1 = CHALLENGE FUNCTION (

NOM_PARA=' INST'

VALE = (0. , - 1.,

PROL GAUCHE=' CONSTANT',

PROL DROITE=' LINEAIRE',

);

1. , 0.,

3. , 1.,

6. , 2.,),

4.2

Function and variables entered in the form of concepts

listr8

It is possible to define this function using concepts of the type

listr8

created by

the intermediary of the operator

DEFI_LIST_REEL

[U4.34.01]:

X-COORDINATE = DEFI_LIST_REEL (BEGINNING = 0. ,

INTERVAL = (_F (JUSQU_A = 1., A NUMBER = 1,),

(

JUSQU_A

3.,

NUMBERS

1,),

(

JUSQU_A

6.,

NUMBERS

1,),)

)

ORDINATE = DEFI_LIST_REEL (BEGINNING = - 1. ,

INTERVAL = (_F (JUSQU_A = 0., A NUMBER = 1,),

(JUSQU_A

1.,

NUMBERS

1,),

(JUSQU_A

2.,

NUMBERS

1,),)

)

EX_2 = DEFI_FONCTION

(NOM_PARA = “INST”,

VALE_PARA

X-COORDINATE,

VALE_FONC

ORDINATE,

PROL_DROITE

“CONSTANT”,

PROL_GAUCHE

“LINEAR”,

)

Note:

The second example is obviously quite intricate to define the function suggested.
We wanted only to highlight the principle of use of the possibility
offered.
The aforementioned becomes interesting when one uses functions defined in large
a number of points.
Another reason to use the definition by

DEFI_LIST_REEL

is when the lists are

necessary like argument for another operator: (list of the moments of a calculation
evolutionary

THER_LINEAIRE

DYNA_LINE_TRAN

…),

this avoids duplication then

information.