Mesh Method

These are LaGriT input command files (.lgi) and output report files (.out.txt) used in creating this mesh.
The output files are copied from the LaGriT outx3dgen file generated from running a command .lgi file,
and report information about the data and mesh, and Success or Error in the routines.
These instructions assume an advanced user of LaGriT and some familiarity with python scripts.
The complete set of scripts and LaGriT input files are in lagrit_input_files directory of archive.
The complete set of outx3dgen files from LaGriT are copied to *.out.txt in lagrit_output_files directory of archive.


Setup Directories and Files

In directory work_dir
mkdir input
  link DEM elevation data to input/lidar.inp
  link polygon data to input/poly1000*.avs
mkdir lagrit_files
cp lagrit_input_files/*lgi lagrit_files
cp lagrit_input_files/*py work_dir 
cp lagrit_input_files/*sh work_dir 
mkdir output_surf_mesh
mkdir output

Create Mesh Using Polygons and DEM Data

Scripts are run from directory work_dir

Input Data are in directory work_dir/input

Output Files are written in directory work_dir/output

LaGriT Files are read and written in directory work_dir/lagrit_files

There are 2 Steps using python scripts. Normally Step 1 is run once, with output files saved for re-use to work_dir/output_surf_mesh.
If any of the Step 1 scripts are changed, then the Step 1 should be re-run.

Scripts will over-write files in work_dir/output, use this as your work directory

Path 1: Run python script surf_mesh.py

Path 2: Run python script mesh_adjoin.py (edit to select polygon numbers)

rm output/*
rm output_surf_mesh/*
./surf_mesh.py
grep ERR output/*txt
grep Err output/*txt
cp output/* output_surf_mesh/
./mesh_adjoin.py
grep ERR output/*txt
grep Err output/*txt



Description of LaGriT Files from This Workflow

From Run surf_mesh.py and mesh_adjoin.py above. This will create all the LaGriT input and output files.
Edit and run LaGriT outside the python scripts to build a stacked prism mesh from selected subset of polygons.

Input are the LaGriT command files filename.lgi       Output are the LaGriT report files filename.out.txt


Step 1: Create Ice Object(s) from Polygons (make_poly.lgi).

Each polygon uses the same command file.
Input
Polygon #1:  Output
Note: A LaGriT report file is written for each polygon. To view the report for a particular polygon, change the # of the polygon in the link: make_poly<enter_your_number>.out.txt

Step 2: Merge all the ice objects created in Step 1 (merge_ice.lgi)

This command file will work for single or multiple polygons.
Input      Output

Step 3: Create and stack layers into full mesh (stack_full_poly.lgi)

The triangulated polygon surfaces are stacked and refinment added between the surfaces. The result is a 3D prism mesh.
Input       Output

Step 4: Interpolate Ice Material on to Full Stacked Mesh (interpolate_icewedge.lgi)

This will use the 3D ice object to overwrite materials in the stacked mesh.
Input       Output

Step 5: Create facesets and write final Exodus files (write_exo.lgi)

This will reorder materials for ExodusII from 1 to n and create face sets for ExodusII boundary sidesets.
Input       Output