eusoubrasileiro / geonumerics Goto Github PK

• Choose what methods make available to python
• Recompile the code of dsp library to make static library.
• Use ctypes or any other method easier than swig to wrap-up the library for python.
• re-write the tests and cookbook examples

The final goal of the project now is perform pos-stack time migration on the marmousi data set. Having time perform the pre-stack time migration on the same data set. Understanding then all related steps.

Solver for 2D banded sparse matrix:

http://pysparse.sourceforge.net/fact.html

May increase considerably memory usage and performance.

Sparse matrix formats:

http://pysparse.sourceforge.net/spmatrix.html#example-2d-poisson-matrix

Implement sponge or perfect match layer in explicit modeling code.
Also Cerjan dumping.

What steps will reproduce the problem?

1. Running WaveFd.Exp2DWave following the required convergence criteria.

What is the expected output? What do you see instead?
To find the wave progressing through time and fading according its time length, for example, a wavelet of 50 ms should vanish from its original position after 60ms, for example. Being found somewhere else ahead.

Look after other implementations (Leo) and also post in stack exchange scicomp.

Rewrite the code and clean it up.

Is there something am I missing why am i having dispersion??
Though propagation seams correct, we can see dispersion in space, wave width increasing with time and energy peak decreasing ( space differences??)

Finish implementation including energy injection.

Test in with synthetic triangle model.

• finish documentation for implicit 2d wave equation blog

Recommended books from scicomp:

Finite Difference Schemes and Partial Differential Equations, Second Edition
John C. Strikwerda

Finite Difference Methods for Ordinary and Partial Differential Equations: Steady-State and Time-Dependent Problems (Classics in Applied Mathematics) [Paperback]
Randall LeVeque (Author)

Solving Ordinary Differential Equations II: Stiff and Differential-Algebraic Problems (Springer Series in Computational Mathematics) (v. 2) [Hardcover]
Ernst Hairer (Author), Gerhard Wanner (Author)

Paper about explicit methods:

http://www.sciencedirect.com/science/article/pii/S0021999104001925

Document code and create site style documentation using sphinx-doc.org.
The doc string must contain formulas or whatever in sphinx rst format.

Honor model based on D. Hale and Leo Uieda.
Wavelet sampled at run time and easy manipulation for analytical solution.

Use a picture to create a velocity matrix, find out how and implement, to test with wedge model....

Application on Paraná Basin (1D symmetry Paleozoic Basin?)

• Model 3D model with 2D acquisition to see effect
• Also test effect of crooked acquisition

• Look after solution to find why there is so much exponential growth.
  Source might not be a reason due that fact that implicit is working perfectly.
  Should after last trials post on stackoverflow.

• To find one or to make one.
• Use madagascar or Seismic UNIX to plot the results.

:: For future steps to play with migration after.

old course store in documents... test upwind discretization.

and check if its perfectly working, seams to be though.

To create animations use the following to create a temp folder avoiding permission issues.

http://stackoverflow.com/questions/847850/cross-platform-way-of-getting-temp-directory-in-python

• indexes must be correct by +2/-2 due unused region due 4th order space.
  • the source or any indexed position must correct for unused regions [0:2,:], [:-2,:], [:,0:2], [:,-2:]
• the real calculation grid is (nx+2*pad-4, nz+pad-4)

• Implement and use, 4th order, expression (7)
• Use cython for loop
• Test with marmousi already download from ifp site in bookmarks, also devpython path

Lax Wandroff Document and find convergence limits 1D