CWP Software Update: 10/25/91  (14th edition)Distribution Notes:------------------A new release of the CWP C free software is now availablevia anonymous ftp (138.67.22.6)!Installation should be much easier, due to yeoman efforts by John Stockwell.All of cwp, par, seismic, xplot, psplot, Xcwp and su are installed afteryou follow the instructions in the file README_TO_INSTALL.  There is stillthe potential for problems caused by non-ANSI C variations of some vendors(and, alas, by our goofs).Thanks to many people who have suffered through installs of previousreleases and have kept their tempers sufficiently to send us detailednotes.  In particular, Dean Witte of Chevron sent a list of adaptationsfor Cray Unicos and Richard Verm of Geophysical Development Corporationsent us notes for Sun SPARC.  Another recent port was made by BerendScheffers, TNO Institute of Applied Geoscience (Delft) to DEC.  Wherepossible, I have made changes to avoid the pitfalls described bythese and earlier writers.The file cwp.tar.Z now includes a third directory, seismic, in additionto the cwp and par directories.  At this time, seismic has only the codevelconv.c (formerly housed in .../par/main), but as they say in the ads,"watch this space".The file plot.tar.Z now includes Xcwp in addition to xplot and psplot.cwp.h has been cleaned up.  While this is a good step for the longrun, it unfortunately means that SU codes won't compile if youre-install cwp.tar, and don't update su.tar as well (potentiallyother directories are also at risk).Here are the major points:1. We eliminated or demoted (to par.h or su.h) some typedefs   and #defines.  The one that will make the most trouble is	typedef char* string   I tried to find all uses of this, but to err is human.   If I left any in, you can put the above typedef in the   files that need it or --recommended-- replace "string"   by "char *" as in:	string sdoc	to:	char *sdoc   Less likely, but also possible, trouble spots are files   that have "bool", "bmstate", ...  Send me a flame if   you find any compilation woes along these lines.   2. I also moved any #include file that wasn't ANSI C out of cwp.h (into   par.h).3. I eliminated the parenthesized system error message that errpkge/err   gave.  We generally don't make direct system calls, so the system message   is usually too far removed from the error to be helpful ("tty not a   typewriter", etc.).4. par.h had an include for fcntl.h that repeated the one in cwp.h.  On some   older Unixes this could cause problems. New Programs------------suresamp - Resample in time	subsample, oversample, time gating done with 8 point	sinc interpolation. (Jack)Note 1: as a consequence, suus (subsampling) has been removed from SU.Note 2: as a consequence, suwind no longer does time gating.     Note 3: is just the su version of Dave's .../par/main/resamp.c sustolt - Stolt migration for stacked data or common offset traces (Dave)susynlv - Kirchhoff synthetic data for a linear v(x,z) medium (Dave)sunsimage - new su driver for nsimage (mainly for local NeXT users) (Jack)suvibro - create vibroseis wavelet (Michel Dietrich)Minor fixes/Updates-------------------	.../su/main/suaddnoise	.../su/main/sudmofk	.../su/main/sugain	.../su/main/suilog	.../su/main/sumute	.../su/main/suop2	.../su/main/sustack	.../su/main/suvelan	.../su/main/suwind	.../su/shell/updatedoc	.../su/examples/Decontest	.../su/examples/SegyreadNote 1: The bug in sugain caused agc to zero out data when it was small(eg. 10e-10).  There were hints of such a problem for some time, but Inever caught on.  Thanks to Phil Anno and Laura Hale for isolating theproblem and to Craig Artley for solving it.Note 2: I added WMHint to ../xplot/lib/window.c to correct keyboardfocus problem at some external sites.Affected programs: xwigb, ximage, suxwigb, suximageFortran Software----------------cshot -- is a free ray-based modeling package written by	Paul Docherty.  It is based on the Keller-Fawcett-Perera	method.  It comes with 14 sub-directories that successively	illustrate the use of the program using X Windows (plus hints	for adaptation to PostScript).  Available as cshot.tar.Z from	CWP's anonymous ftp (138.67.22.6).  Hardcopy documentation is	available from CWP (free to sponsors, otherwise for a fee of $10).	cxzco -- is a proprietary pre-stack inversion program for common offset	data with arbitrary background velocity in a 2.5D medium.	It comes with 4 demonstration subdirectories.  Availability	is restricted to sponsors of CWP who can get additional	copies by using our sponsor ftp (call 303-273-3557 for	further information or to arrange getting floppy/tape	distribution).Special Free Contribution from Shelby Worley, former CWP student-------------------------------------------------------------------------The package is available by anonymous ftp as rgps.tar.Z and isself-contained.  However, the interface is just like the rest ofthe CWP C mains.  Here's the beginning of the readme.rgps fileincluded with the distribution:RGPS: Reflection Geometry Parameter SolverI. What is the program for?     This program was written to implement a new approach to the most simplenon-trivial reflection problem - a dipping plane reflector with separatedsource and receiver on a horizontal surface.  The user specifies values forfour of the following eleven parameters, which are divided into twocategories: Circle Parametersalpha:  the dipping angle of the reflector. By convention, it is positive        if the z-coordinate increases as the x-coordinate increases along        the reflector. Alpha will be in the range (-90,90).phi:    the angle between the raypath and a normal to the reflector.        Phi will be in the range [0,90).h:      One half the separation between the source and receiver.        H will always be positive.dx:     The offset of the x-coordinate of the specular reflection point        and the x-coordinate of the midpoint between source and receiver.        Dx will be positive if the x-coordinate of the specular point        is smaller than the x-coordinate of the source-receiver midpoint.z:      The depth of the specular reflection point.vt:     The length of the specular reflection path between source and        receiver. Shift Parametersxs:     The location of the "source".  For convenience, this is assumed to        have a smaller x-coordinate than the receiver.xg:     The location of the "receiver".  This value will always be larger        than xs, so that  the equation  2h=xg-xs  is always true.y:      The source-receiver midpoint.x:      The x-coordinate of the specular reflection point.z0:     The depth (z-coordinate) of the reflector under the origin        of the x-coordinates.  Thus, the equation of the reflector is        z = z0 + x*tan(alpha). Z0 may be negative if the plane of the        reflector extends above the surface at the origin.     With these 11 parameters, 330 possible sets of four parameters couldbe chosen. The program will attempt to calculate the value for the otherseven parameters....