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Material / element property handling utilities.


  out = fe_mat('convert si ba',pl);
  out = fe_mat('unit')
  out = fe_mat('unitlabel',UnitSystemCode)


Material definitions can be handled graphically using the Material tab in the model editor (see section 4.2.1). For general information about material properties, you should refer to section 7.3. For information about element properties, you should refer to section 7.4.

The main user accessible commands in fe_mat are listed below


The convert command supports unit conversions to unit1 to unit2 with the general syntax

pl_converted = fe_mat('convert unit1 unit2',pl);
il_converted = fe_mat('convertil unit1 unit2',il);

For example convert from SI to BA and back

 mat = m_elastic('default')
 % convert from SI unit to BA unit
 pl=fe_mat('convert SIBA',;
 % check that conversion is OK
 pl2=fe_mat('convert BASI',pl);

out=fe_mat('unitsystem') returns a struct containing the information characterizing standardized unit systems supported in the universal file format.

CodeIdentifierLength and Force
1SIMeter, Newton
2BGFoot, Pound f
3MGMeter, kilogram f
4BAFoot, poundal
5MMMillimeter, milli-newton
6CMCentimeter, centi-newton
7INInch, Pound force
8GMMillimeter, kilogram force
9TMMillimeter, Newton
9USUser defined

Unit codes 1-8 are defined in the universal file format specification and thus coded in the material/element property type (column 2). Other unit systems are considered user types and are associated with unit code 9. With a unit code 9, fe_mat convert commands must give both the initial and final unit systems.

out=fe_mat('unitlabel',UnitSystemCode) returns a standardized list of unit labels corresponding in the unit system selected by the UnitSystemCode shown in the table above.

When defining your own properties you only need to implement the p_fun PropertyUnitType command to allow support of unit conversion.


pl = fe_mat('getpl',model) is used to robustly return the material property matrix pl (see section 7.3) independently of the material input format.

Similarly il = fe_mat('getil',model) returns the element property matrix il.


r1 = fe_mat('GetMat Param',model) This command can be used to extract given parameter Param value in the model properties. For example one can retrieve density of matid 111 as following
rho=fe_mat('GetMat 111 rho',model);


r1 = fe_mat('SetMat MatId Param=value',model)
r1 = fe_mat('SetPro ProId Param=value',model)
This command can be used to set given parameter Param at the value value in the model properties. For example one can set density of matid 111 at 5000 as following
rho=fe_mat('SetMat 111 rho=5000',model);


The type of a material or element declaration defines the function used to handle it.

typ=fe_mat('m_function',UnitCode,SubType) returns a real number which codes the material function, unit and sub-type. Material functions are .m or .mex files whose name starts with m_ and provide a number of standardized services as described in the m_elastic reference.

The UnitCode is a number between 1 and 9 giving the unit selected. The SubType is a also a number between 1 and 9 allowing selection of material subtypes within the same material function (for example, m_elastic supports subtypes : 1 isotropic solid, 2 fluid, 3 anisotropic solid).

Note : the code type typ should be stored in column 2 of material property rows (see section 7.3).


Similarly, element properties are handled by p_ functions which also use fe_mat to code the type (see p_beam, p_shell and p_solid).


Calls of the form [o1,o2,o3]=fe_mat(ElemP,ID,pl,il) are used by element functions to request constitutive matrices. This call is really for developers only and you should look at the source code of each element.

See also

m_elastic, p_shell, element functions in chapter 8

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