cutde 21.4.1

130 million TDEs per second, Python + CUDA TDEs from Nikkhoo and Walter 2015

cutde

Python + CUDA TDEs from Nikkhoo and Walter 2015

CUDA and OpenCL-enabled fullspace triangle dislocation elements. Benchmarked at 130 million TDEs per second.

See below for usage and installation instructions.

Basics

Howdy! Usage is really simple:

import cutde

disp = cutde.disp(pts, tris, slips, 0.25)
strain = cutde.strain(pts, tris, slips, nu)

• pts is a np.array with shape (N, 3)
• tris is a np.array with shape (N, 3, 3) where the second dimension corresponds to each vertex and the third dimension corresponds to the cooordinates of those vertices.
• slips is a np.array with shape (N, 3) where slips[:,0] is the strike slip component, while component 1 is the dip slip and component 2 is the tensile/opening component.
• the last parameter, nu, is the Poisson ratio.

IMPORTANT: N should be the same for all these arrays. There is exactly one triangle and slip value used for each observation point.

• The output disp is a (N, 3) array with displacement components in the x, y, z directions.
• The output strain is a (N, 6) array representing a symmetric tensor. strain[:,0] is the xx component of strain, 1 is yy, 2 is zz, 3 is xy, 4 is xz, and 5 is yz.

I want stress.

Use:

stress = cutde.strain_to_stress(strain, sm, nu)

to convert from stress to strain assuming isotropic linear elasticity. sm is the shear modulus and nu is the Poisson ratio.

All pairs

If, instead, you want to create a matrix representing the interaction between every observation point and every source triangle, there is a different interface:

import cutde

disp = cutde.disp_all_pairs(pts, tris, slips, 0.25)
strain = cutde.strain_all_pairs(pts, tris, slips, nu)

• pts is a np.array with shape (N_OBS_PTS, 3)
• tris is a np.array with shape (N_SRC_TRIS, 3, 3) where the second dimension corresponds to each vertex and the third dimension corresponds to the cooordinates of those vertices.
• slips is a np.array with shape (N_SRC_TRIS, 3) where slips[:,0] is the strike slip component, while component 1 is the dip slip and component 2 is the tensile/opening component.
• the last parameter, nu, is the Poisson ratio.
• The output disp is a (N_OBS_PTS, N_SRC_TRIS, 3) array.
• The output strain is a (N_OBS_PTS, N_SRC_TRIS, 6) array.

Note that to use the strain_to_stress function, you'll need to reshape the output strain to be (N_OBS_PTS * N_SRC_TRIS, 6).

Installation

Just run

pip install cutde

Then, if you have an NVIDIA GPU, install PyCUDA with:

conda install -c conda-forge pycuda

If not, you'll need to install PyOpenCL. Installing OpenCL is sometimes a breeze and sometimes a huge pain, but it should be installable on most recent hardware and typical operating systems. These directions can be helpful.. I am happy to try to help if you have OpenCL installation issues, but I can't promise to be useful. For me, on an Ubuntu + Intel machine, I just ran:

conda install -c conda-forge pyopencl ocl-icd-system

and everything worked wonderfully.