3. Output filenames and descriptions
The bottom part of the input files describes the types of output requested. Here is an example:
| bottom part of input file | explanation |
| * Run everything else interactively | comment |
| Non-interactive grid specification | specify grid to which output is referred below |
| plane | let this grid be a plane |
| vector | request vector output (note: xyz format is always output) |
| * output coordinate system | specify output coodinate system |
| global | choose global rather than in-plane |
| * output files to create | select whichever output is required (there are many choices, read on) |
| elem | relative displacements on elements |
| displacements | absolute displacements on inspection grid |
| rbr | rigid-body rotations on inspection grid |
| * output file suffix | 4 characters or less |
| t | output file suffix (format allows no more than 4 characters) |
| * Xo,Yo,Zo (Ref. corner),strike,dip,length,width: | specify inspection plane |
| 0 55 0 90 0 59 59 | see below |
| * number of grid points in strike and dip directions: | actually the number of equal divisions along strike and dip |
| 59 59 | see below |
In this example, results will be written with reference to coordinates that define a horizontal plane at the surface whose origin in global coordinates lies 55 km north of the coordinate origin, and that is 59 km along strike and dip. The plane is then divided into 59 intervals along both strike and dip, so that quantities (in the case, components of displacements and rbr) will be written at 1 km spacings. This will yield 60 results along both strike and dip, for a total of 3,600 x 3 displacement results. Displacements of all subelements will also be written to elem files.
Output files formats can be 'xyz' (column) or 'vector' (matrix) format, and they are referenced to either the inspection grid or the elements themselves.
'xyz' format lists each component of the calculated quantity in column format next to its location in either global or in-plane coordinates.
The first three columns are the x, y, and z locations in global coordinates (it's usually better or easier to use global coordinates), the next columns are deformation quantities calculated at this location.
The equivalent vector output comprises three matrices, one for each component of displacement (or whatever quantity is being output): disp1, disp2, and disp3, where 1, 2, and 3 are cryptic mnemonics for x, y, and z. Locations are implicit in the position of the matrix elements. Vector output is useful for plotting purposes (using something like MATLAB or Spyglass) and for quick visual inspection of the results.
Remember that the vector files elem.. are written
in matrix format (with (1,1) at top-left, etc.), in contrast to their
order in the input file. There are some applications in which you might
want to put the results of one model run back into another model. A few
MATLAB commands to do this one elem block at a time are:
3. Output filenames and descriptions
A description of the some of the output files and the type of output is given below. Global coordinates are referenced if the quantities have x, y, or z as part of their output name (e.g., Exy, Exx, etc.) In-plane coordinates are referenced if s, d, or n (strike, dip, or normal) are part of the output file names (e.g., Esd, Ess, etc.). To avoid a cluttered look, we refer always to the global coordinates in the list below.
The underlined word or portion of a word is the
name of the output file as it should be entered in the input file. For
example, if you want the displacement gradient tensor, enter grad, or
for rigid-body rotations, enter rbr.
Each filename, in italics below, whether output in
xyz or in vector format carries a suffix (e.g., strainten.<suffix>).
For clarity, this is not indicated below.
Although we label these quantities as simple
strains, they ARE indeed strain tensor components.