Yaxun's library
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ylib will include:
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1. basic geometry calculation for 2-D and 3-D migration(finished), modeling (shot profile)
2. basic one-way (finished) and two-way extrapolators
3. green's function (finished)
4. Hessian (finished)
5. Wave-equation tomography(planning)

I plan to have this finished at the end of winter break, Jan. 2008

New task: Jan. 2008
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1. FFD with optimized coefficients
2. FFDPI if have time
3. Combine my two-way code (slowly)
4. Tomography (finished, Aug. 08)
5. Gauss-Newton(or Quasi-Newton, or Levenberg Marqurdt) one-way waveform inversion, with explicit Hessian by random phase encoding (planning, Aug. 08)
6. Finite-difference dip filter for angle gathers (planning, Aug. 08)

Update: Aug. 2008
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1. Postack wave-equation tomography (finished)
2. Prestack wave-equation tomography (finished)
3. Wave-equation tomography for generalized source functions, planewaves, composite sources (finished)
4. Added B-spline basis function modules (finished)
5. Prestack residual migration (finished)
6. Prestack differential residual migration (finished)
7. Out of core DSO operators (finished, needs refining)

New task: Aug. 2008
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1. More efficient B-spline basis function, recursive filtering
2. Out of core library, based on Paul's OClib
3. L-BFGS with bound constrains
4. Out of core conjugate gradient
5. Scattering and dip angle gathers before imaging