Month: January 2015

Acoustic staggered grid in IWAVE

January 31, 2015 Documentation No comments

A new paper is added to the collection of reproducible documents:
Acoustic staggered grid modeling in IWAVE

IWAVE is a framework for time-domain regular grid finite difference and finite element methods. The IWAVE package includes source code for infrastructure component, and implementations of several wave physics modeling categories. This paper presents two sets of examples using IWAVE acoustic staggered grid modeling. The first set illustrates the effectiveness of a simple version of Perfectly Matched Layer absorbing boundary conditions. The second set reproduce illustrations from a recent paper on error propagation for heterogeneous medium simulation using finite differences, and demostrate the interface error effect which renders all FD methods effectively first-order accurate. The source code for these examples is packaged with the paper source, and supports the user in duplicating the results presented here and using IWAVE in other settings.

Program of the month: sfmf

January 30, 2015 Programs No comments

sfmf applies a median filter on the first dimension of the input.

The size of the filter window is controlled by nfw= parameter. The following example from tccs/medianfilter/dragon shows field seismic data before and after 11-point (nfw=11) median filtering combined with bandpass filtering. For time-variant median filtering, see sftvmf. To simply output the median of the first axis, use sfmedian.

10 previous programs of the month: