3. Operands#
3.1. Operand DIMENSION#
◊ DIMENSION = n
Dimension of the spectral density matrix, stored in an interspectrum table (tabl_intsp).
3.2. Keyword PAR_FONCTION#
♦ PAR_FONCTION =
Keyword factor, allows you to define a term (i, j) of the interspectral matrix based on function_c concepts already defined.
3.2.1. Operands NUME_ORDRE_I, NUME_ORDRE_J#
NUME_ORDRE_J = j
Couple of indices (row, column) of the matrix on which we will assign a function.
These operands are exclusive with operands NOEUD_I NOEUD_J NOM_CMP_I NOM_CMP_J.
3.2.2. Operands NOEUD_I, NOEUD_J, NOM_CMP_I, NOM_CMP_J#
NOEUD_J = nd_j [node] NOM_CMP_I = ncmp_i [Kn] NOM_CMP_J = ncmp_j [Kn]
These operands correspond to the names of the nodes and components (row, column) of the matrix where a function will be assigned.
These operands are exclusive with operands NUME_ORDRE_I NUME_ORDRE_J.
3.2.3. Operand FONCTION#
funct is a function_c concept.
3.3. Keyword KANAI_KAJIMI#
Keyword factor, allows you to define a spectral density function using the Kanai and Tajimi model. This spectral density function corresponds to that of filtered white noise [bib2].
The three parameters of the spectral density of the KANAI_TAJIMI model are given: damping, frequency, and level.
3.3.1. Operands NUME_ORDRE_I, NUME_ORDRE_J#
NUME_ORDRE_J = j
Pair of indices (row, column) of the interspectral matrix. Since there is no spectral coherence model, the Kanai-Tajimi model only allows you to create auto-spectra. It is therefore necessary to choose i = j (in general, we will choose n=1 and i=j=1 here).
These operands are exclusive with operands NOEUD_I NOEUD_J NOM_CMP_I NOM_CMP_J.
3.3.2. Operands NOEUD_I, NOEUD_J, NOM_CMP_I, NOM_CMP_J#
NOEUD_J = nd_j [node] NOM_CMP_I = ncmp_i [Kn] NOM_CMP_J = ncmp_j [Kn]
These operands correspond to the names of the nodes and components (row, column) of the matrix where a function will be assigned. In the case of the Kanai-Tajimi model, we choose NOEUD_I = NOEUD_J and NOM_CMP_I = NOM_CMP_J.
These operands are exclusive with operands NUME_ORDRE_I NUME_ORDRE_J.
3.3.3. Operands AMOR_REDUIT/FREQ_MOY/VALE_R/VALE_C#
◊ FREQ_MOY = FMOY ◊/VALE_R = valr /VALE_C = valc
fmoy and amor are the natural frequency and the reduced damping of the filter. The level can be given in complex or real form.
3.3.4. Operands INTERPOL/PROL_GAUCHE/PROL_DROITE#
For each function, the classical parameters that condition the interpolation and extrapolation of the function produced are given. The options as well as the by default values are listed on page 2.
◊ PROL_GAUCHE ◊ PROL_DROITE
For more details see [§3.4] and [§3.5].
3.3.5. Operands FREQ_MIN/FREQ_MAX/PAS#
The parameters of frequency discretization are given.
◊ FREQ_MAX = fmax ◊ PAS = step
3.3.6. Operands PROL_DROITE and PROL_GAUCHE#
◊ PROL_DROITE and PROL_GAUCHE =
Define the type of extension to the right (left) of the variable’s domain of definition:
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for an extension with the last (or first) value of the function, |
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for an extension along the first defined segment (PROL_GAUCHE) or the last defined segment (PROL_DROITE), |
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if extrapolation of values outside the domain of definition of the parameter is prohibited (in this case if a calculation requires a value of the function outside the domain of definition, the code will stop in a fatal error). |
For example:
PROL_DROITE = “CONSTANT”, PROL_GAUCHE = “CONSTANT”
PROL_DROITE = “LINEAIRE”, PROL_GAUCHE = “EXCLU”
Note:
The type of extension and interpolation are independent of each other.
3.3.7. Operand INTERPOL#
◊ INTERPOL =
Type of interpolation of the function between values in the domain of definition of the function: one type for the interpolation of the parameter and one for the interpolation of the function. This is achieved by providing a list of texts from:
“LIN”: |
linear, |
“LOG”: |
logarithmic, |
Note:
If only one value is specified, it is taken into account by both the interpolation of the parameter and the function. INTERPOL = “LOG” is equivalent to (“LOG”, “LOG”) .
3.4. Keyword CONSTANT#
Keyword factor that makes it possible to define a spectral density function corresponding to a band white noise (constant spectral density over the frequency band in question).
All the keywords under this factor keyword have the same meaning as for the factor keyword KANAI_TAJIMI except AMOR and FREQ_MOY which don’t make sense here.
3.5. Operand TITRE#
◊ TITRE = title
Title is the title of the calculation to be printed at the top of the results. See [U4.03.01].
3.6. Operand INFO#
◊ INFO =
1: |
no printing. |
2: |
impression of the characteristics of the defined interspectral matrix. |