This method is much closer to MED file organization than basic MEDLoader API. All MED file concepts are exposed to the user. As a consequence, this advanced API is lead to change with MED file data model enhancement.
In reading mode, the user can scan entirely and directly the content of its MED file as it is organized in its MED file. Inversely, in writing mode, the user can describe its data in the same way that MED file does.
meshDimRelToMax
. Each time This parameter appears in API, it will have the semantic explain here. The value of the parameter meshDimRelToMax
is at most in {0,-1,-2,-3}. This relative value specifies a level relative to value returned by myMedMesh->getMeshDimension()
.A mesh containing MED_TETRA4, MED_TRI3, MED_QUAD4 and MED_POINT1 has a meshDimension equal to 3. For meshDimRelToMax
equal to 0 the user will deal with cells whose type has a dimension equal to 3+0, that is to say here MED_TETRA4. For meshDimRelToMax
equal to -1 the user will deal with cells witch dimension equal to 3-1 that is to say MED_TRI3 and MED_QUAD4.
An important method is getNonEmptyLevels()
method. It returns all non empty levels available. In the previous example, this method will return {0,-1,-3}. -2 does not appear because no cells with dimension equal to 1 (3-2) appear in MED file mesh (no MED_SEG2 not MED_SEG3).
meshDimRelToMax
there is notion of meshDimRelToMaxExt
. meshDimRelToMaxExt
is simply an extension of meshDimRelToMax
for nodes.The parameter of meshDimRelToMaxExt
appears in umesh advanced API of MEDLoader with the following semantics.
Some of MED file concepts are available both for cells and nodes, (for example families, groups, numbering ) that's why for a simpler API this concept has been introduced. meshDimRelToMaxExt
parameter can take a value in at most {1,0,-1,-2,-3}. 1 stands for node and 0,-1,-2,-3 has exactly the same semantic than those described in meshDimRelToMax
decribed before.
renum
. This parameter by default in advanced MEDLoader API is set to true
. This parameter indicates if the user intend to take into account of the renumbering array of cells of the current MED file mesh. If no renumbering array is defined, this parameter is ignored by MEDLoader.If such renumbering exists and the renum
parameter is set to true
, then the renumbering is taken into account. This is exactly the behaviour of basic MEDLoader API. If the user expects to ignore this renumbering even in case of presence of renumbering array, false should be passed to renum
parameter. The parameter renum should be set with cauton for users concerned by cells orders.
mode
during writing. The available values for the parameter mode
are :write
method has been calles.Contrary to the basic MEDLoader API, here after reading process, the user has to deal with a new instance of class that fits the MED file model. To access to a MEDCoupling mesh the user should request this class instance.
The class that incarnates Read/Write mesh in MED file is ParaMEDMEM::MEDFileUMesh.
First of all, like basic MEDLoader API, only MEDfile files whose version >= 2.2 are able to be read with advanced API.
To read a mesh having the name meshName
in file fileName
the following simple code has to be written :
If the user do not know the name of the mesh inside MED file 'fileName' the following code should be written :
In this case the first mesh (in MED file sense) found in fileName
file will be loaded.
Now the user can ask for mesh dimension of of myMedMesh
instance by calling myMedMesh->getMeshDimension()
. This method returns the highest level of present cell in MED file mesh myMedMesh
. This returned integer is computed and not those contained in MED file that can be invalid.
meshDimRelToMax=mdrm
: simply callmyMedMesh->getMeshAtLevel(mdrm)
myMedMesh->getLevel0Mesh()
or myMedMesh->getLevelM1Mesh()
, or myMedMesh->getLevelM2Mesh()
depending on the value of mdrmgetFamilyArr
method or getFamiliesArr
getFamily
method or getFamilies
getGroupArr
method or getGroupsArr
getGroup
method or getGroups
getFamilyFieldAtLevel
retrieves for a specified extended level the family id of each cell or node.getNumberFieldAtLevel
returns, if it exists for a specified extended level, the family id of each cell or node. If it does not exist an exception will be thrown.An important point is that families and groups are not sorted in MED file. No sort is stored in MED file explicitely for Groups and Families. Advanced MEDLoader API, uses the same order than underlying mesh at specified level.
Here a typical use of MEDCouplingUMesh instance.
The use is very symetric to reading part. It is possible to either build a MEDFileUMesh instance from scratch, or to work with an existing instance coming from a loading from a file.
One important point is that coordinates of a mesh are shared by all cells whatever their level. That's why the DataArrayDouble instance should be shared by all MEDCouplingUMesh used in input parameter of set* methods. If the user intend to build a MEDFileUMesh instance from scratch, a call to setCoords
should be done first.
Generally speaking traduce get* methods with set* methods have corresponding write semantic.
Some differences still exist :
setMeshAtLevel
, setMeshAtLevelOld
simply call setMeshAtLevelGen
with repectively newOrOld
parameter set to true and false. These method specifies if a renumbering computation is needed or not. setMeshAtLevelOld
is faster than setMeshAtLevel
because no renumbering computation is done. If the user is not warranty about the order of its meshes to enter it is better to use setMeshAtLevel
method.