sfgrey3 generates "cube" plots from 3-D data.

A cube plot displays sections from a 3-D cube as faces of the cube.

Some of the options specific to this kind of display are:

**flat=**

The **flat** parameter tells **sfgrey3** whether to display the cube as a flat image or in a 3-D projection. The default is **flat=y**. The following example from bei/fld/cube displays the same input data with both options:

**frame1=, frame2=, frame3=**

The frame parameters select the slices from the cube to be displayed in the plot. The default is to take the first slice from the vertical and the out-of-plane axis (**frame1=0 frame3=0**) and the last slice from the horizontal axis (**frame2=n2-1**). In the following example from geo384w/hw3/gulf, the data size is **n1=1000 n2=250 n3=48** and the frame parameters are **frame1=500 frame2=160 frame3=10**:

**point1=, point2=**

The **point1= and point2=** parameters control the aspect ratio of the cube by specifying the ratio (from 0 and 1) that the front face of the cube takes from the plot in the vertical and the horizontal dimension, respectively. The default is **point1=0.5 point2=0.5**. The following example from sep/plane/qint has **point1=0.85 point2=0.74**:

**movie=**

The **movie** parameter allows the user to create a movie looping over slices in a cube instead of a static picture. The value of the parameter (from 1 to 3) indicates the axis for looping or 0 (the default) for no movie. The frame increment in the movie is controled by **dframe=**. The following example from cwp/geo2009TTIModeSeparation/tti3 uses **movie=1** to loop over the vertical axis:

To generate a movie out of 4-D data, you can use

sfgrey4. Here is an example:

### Previous programs of the month:

sfderiv applies the first derivative filter. The algorithm implemented in this program is described in the paper Pei, S.-C., and P.-H. Wang, 2001, Closed-form design of maximally flat FIR Hilbert transformers, differentiators, and fractional delaye

Weblog:Madagascar development blogTracked:Jun 02, 06:46sfdip estimates a local slope (dip) using the plane-wave destruction algorithm. The dip is measured in time samples. If α is the dip angle, then the output of sfdip corresponds to the dimensionless quantity p=tanα. The following example

Weblog:Madagascar development blogTracked:Jun 04, 05:46sffft3 implements a complex-to-complex Fast Fourier Transform (FFT) along an arbitrary axis. The FFT library that Madagascar uses is KISS FFT, created by Mark Borgerding. KISS stands for Keep it simple, Stupid! KISS FFT may not be as fast as FFTW but i

Weblog:Madagascar development blogTracked:Jul 08, 12:34Previous programs of the month:sffft3sfdipsfderivsfgrey3sfspectrasfnoisesfgraphsfclipsfagcsfenvelopesfcontoursfsmooth

Weblog:Madagascar development blogTracked:Sep 03, 14:02sfpick performs automatic picking from semblance-like panels. The underlying algorithm is described in Appendix B of the paper Velocity analysis using AB semblance and is inspired by the method of virtual endoscopy in medical imaging. The following

Weblog:Madagascar development blogTracked:Sep 08, 16:07sfiwarp performs mapping between different coordinates. If you have sampled functions f(x) and y(x), sfiwarp with inv=y (the default) finds sampled f(y). If inv=n, sfiwarp takes f(y) and y(x) and finds f(x). In both cases, the sampled y(x) function is sup

Weblog:Madagascar development blogTracked:Sep 09, 12:52sfpick performs automatic picking from semblance-like panels. The underlying algorithm is described in Appendix B of the paper Velocity analysis using AB semblance and is inspired by the method of virtual endoscopy in medical imaging. The following

Weblog:Madagascar development blogTracked:Sep 09, 12:52sfkirmod is a program for modeling seismic reflection data using the Kirchhoff method. According to this method, the reflection response is computed by integrating over the reflector surface. For a theoretical derivation, see, for example, Haddon, R. A

Weblog:Madagascar development blogTracked:Oct 13, 19:46sfbandpass implements bandpass filtering using the Butterworth algorithm. The desired bandwidth is specified by low and high frequencies (in Hertz) flo= and fhi=. A continuous low-pass Butterworth filter is given by The actual filtering is imp

Weblog:Madagascar development blogTracked:Nov 18, 13:45sfhalfint implements half-order integration or differentiation, a filtering operation common in 2-D imaging operators such as as slant stacking or Kirchhoff migration. By default, sfhalfint performs half-order integration. To apply half-order different

Weblog:Madagascar development blogTracked:Jan 06, 16:58sfricker1 implements 1-D convolution with the Ricker wavelet. The following example from rsf/rsf/wedge shows convolution modeling with a wedge model using sfricker1. The convolution is implemented in the frequency domain, where the Ricker wavele

Weblog:Madagascar development blogTracked:Jan 18, 12:49sfricker1 implements 1-D convolution with the Ricker wavelet. The following example from rsf/rsf/wedge shows convolution modeling with a wedge model using sfricker1. The convolution is implemented in the frequency domain, where the Ricker wavele

Weblog:Madagascar development blogTracked:Jan 19, 12:00sfpwd implements plane-wave destruction, a filter that attenuates locally plane-wave events, as described in the paper Applications of plane-wave destruction filters. The following example from jsg/diffr/gom shows a seismic section before and after an

Weblog:Madagascar development blogTracked:Feb 09, 16:20The example in rsf/tutorials/slicing reproduces the tutorial from Evan Bianco of simple data slicing. See also: Program of the month: sfgrey3Documentation for sfwindow Madagascar users are encouraged to try improving the results.

Weblog:Madagascar development blogTracked:Aug 20, 15:47