Calculate section loads from Grid Point Force Balance.
msection=sectionLoads(gpfb,group,fem)
msection=sectionLoads(gpfb,group,fem,'silent')
SECTIONLOADS computes the equivalent loads at the given point for a section defined by a group with list of nodes and a list of elements (on one side of the section). By default, resultants are calculatedin the basic coordinate system about the geometric center of the nodes in the group. If a coordinate system also exists in the group, the resultants are about the coordinate system origin and in the coordinate system directions. The group can be an array of imat_group, in which case it returns a cell array of resultant matrices.
GPFB is an imat_result containing Grid Point Force Balance Data. This is identified by a DataLocation of Data On Elements At Nodes and a ResultType of Reaction Force. Any results supplied that are not Grid Point Force Balance are removed before processing with a warning.
GROUP is an array of imat_group with nodes, elements, and optionally a coordinate system. If a coordinate system exists in the group, the resultants are calculated about the coordinate system origin and in the coordinate system directions.
FEM is an imat_fem containing the nodes referenced in GROUP.
By default only element forces are included in the section load calculation. To include SPC (reaction) forces as well, pass in the string 'spc'. To include MPC forces, pass in the string 'mpc'. To include applied loads, pass in the string 'applied'. To include forces due to X2GG DMIG input, pass in the string 'x2gg'. To include forces due to FRF components (external or bulk superelement), pass in the string 'frf'. Please note that if the results in GPFB are from Nastran, the non-element forces (e.g. MPC) are the resultant forces due to all of each particular entity type on a given node and not the contributions of individual non-element entities. Because of this, GROUP does not need to include elements when computing section loads based on non-element forces if you only want the contributions from non-element entities such as MPC and SPC.
'silent' is an optional input string. Supplying it suppresses output from SECTIONLOADS.
MSECTION is a 6xNMODES array containing modal section loads about the given point. If multiple groups are provided in GROUP, MSECTION is an NGROUPx1 cell array containing the section load results for each group.
The string 'as_fn' directs SECTIONLOADS to return the section loads as a 6x1 imat_fn for each group.The string 'as_shp' causes SECTIONLOADS to return the section loads as an NRESx1 imat_shp for each group, where NRES is the number of results in GPFB. These two inputs are mutually exclusive.
'no_cell' is an optional input string that causes the output to be returned as a single output type instead of a cell array if GROUPS contains more than one group. For numeric output, MSECTION is a 6xNMODESxNGROUPS array containing modal section loads about the given point. For imat_fn output, MSECTION is a 6xNGROUP imat_fn. For imat_shp output, MSECTION is a NSHPxNGROUP imat_shp.
FEMOUT is an IMAT_FEM containing the node and coordinate system defining the point about which the results are calculated. The node ID is one more than the maximum node ID in FEM.