# XDMF_EXPORT command¶

Python syntax for XDMF export reads:

XDMF_EXPORT (solfec, time, path | subset, attributes)

Export results in XDMF format. In ‘WRITE’ mode only the geometry at time $$t=0$$ is saved, while arguments time and attributes are ignored.

• solfec – SOLFEC object;

• time – time instant, e.g. t0, a collection of time instants, e.g. [t0, t1, t2, …, tN], or a time interval, e.g. (t0, t1);

• path – output path to the directory that will contain the XDMF markup file(s) and a HDF5 data file; e.g. ‘/tmp/sim0’ will possibly result in a /tmp/sim0/sim0_grids.xmf, /tmp/sim0/sim0_constraints.xmf, /tmp/sim0/sim0_spheres.xmf markup files and a /tmp/sim0/sim0.h5 data file output;

• subset – specification of a subset of exported bodies; a string can be used to define a POSIX regular expression 1 that will be matched against body labels; a list of body objects or integer body identifiers can be used [body1, body2, id3, id4, body5, …] mixed up in an arbitrary manner; or a tuple specifying extents of a bounding box can be used (xlow, ylow, zlow, xhigh, yhigh, zhigh), which the bounding boxes of exported bodies overlapped at time t=0; also a list of an arbitrary combination of those can be used, e.g. [‘BOD*A’, 123, body1, body2, 256, (0, 0, 0, 1, 1, 1), ‘KEY??7’, (3, 3, 3, 4, 4, 4)] defines two labels, two integer body ids, two body objects, and two bounding boxes, that together define a subset of bodies that will be used during export;

• attributes – list of export attributes; default [‘DISP’, ‘VELO’, ‘REAC’, ‘GAP’]; available attributes are ‘DISP’ (body displacement), ‘VELO’ (body velocity), ‘STRESS’ (body stress), ‘REAC’ (constraint reactions), ‘RELV’ (relative constraint velocities), ‘GAP’ (contact gaps); a non-optional scalar attribute ‘BID’ (body identifier) is always included with exported geometry;

Currently implemented features:

• Export of MESH and CONVEX shape based bodies into a <path>_grids.xmf file.

• Export of constraints into a <path>_constraints.xmf file.

• Expot of SPHERE shape based bodies into a <path>_spheres.xmf file.

Currently missing features:

• Export of ELLIP shape based bodies.

In the following section we give an example of an application of the above command.

1

POSIX regular expressions