rayinvr.doc

利用fortran写的实现2D射线追踪的源代码！运行于linux下！

itxbox - plot only those calculated and observed travel times that
   have distances between xmint and xmaxt and times between tmin
   and tmax (default: 0)

idata - plot the  observed travel time  picks from the  file tx.in 
   (1 or -1), or plot only those picks used in the inversion if invr=1 
   (2 or -2); the observed data are represented by vertical bars with 
   a height of twice the corresponding uncertainty specified in the 
   file tx.in if idata>0, or by symbols of height symht if idata<0
   (default: 0)

isep - plot the model and rays and travel times in the same plot 
   frame (0), separate plot frames (1), plot the model and rays and
   travel times in a separate plot frame for each shot (2), or plot
   the model and rays in separate plot frames for each shot followed
   by the travel times in separate plot frames for each shot (3)
   (default: 0)
   Note: the value of isep may be changed during a program run with
         entry from the keyboard of the values 0, 1, 2 or 3 between
         plot frames when a <CR> is needed to continue; entering "s"
         will terminate the program run

ibreak - an array corresponding  to the ray groups  listed in the 
   array ray to split travel  time-distance curves into prograde  
   and retrograde segments when plotting with itx=1, and to increment 
   the integer code by one in the file tx.out when changing from  a 
   prograde to retrograde segment or  vice versa if itxout=1
   (default: 1)

iszero - plot the calculated and observed  travel times as if all 
   shot points were at 0 km and  the rays travelled left to right  
   (default: 0)

itxout - write the  calculated travel time-distance  pairs to the  
   file tx.out;  the  integer  code  identifying  each  pick  is  
   determined by the array ibreak if itxout=1 or the array ivray  
   if itxout=2 or 3; if itxout=3, the calculated travel times are
   interpolated to the observed receiver locations (invr=1 must be
   used if itxout=3, if not, itxout=2 is used) (default: 0)
   Note: there appears to be a bug with itxout, itx=itxout may be
         necessary for correct results

idump  -   write  detailed   velocity  model   and   ray  tracing   
   information to  the file  r2.out  and the  namelist parameter  
   values to the file n.out; mainly for debugging (default: 0)
   Note: using idump=1 will greatly slow down the run time
 
isum -  write  a short  summary  about the  rays  traced  and the 
   velocity model to the screen (1), also write the travel time 
   residuals and chi-squared values for each phase and shot to the  
   file r1.out (2), and to the screen (3) (must use invr=1 for 
   isum>1) (default: 1)

istep - pause after each ray is plotted writing its take-off angle
        to the screen and waiting until a <CR> is entered before
        plotting the next ray; this is mainly intended to be used in
        conjunction with irays=1 to determine the cause of the 
        failure of the search mode for a particular ray group; 
        entering "s" after any ray will terminate the program run 
        (default: 0)

b) Other plotting parameters:

symht - height of symbols (mm)  used when plotting each point 
   defining a  ray path,  single  point travel  time  curves (if  
   symht=0, single point travel time curves will not be plotted), 
   the calculated travel times if itx=2, or the observed travel
   times if idata<0 (default: 0.5)

velht - the maximum  height of the velocity  values (mm) when  
   ivel=1 or -1 is equal to velht*albht (default: 0.7)

nskip - the first nskip points  (step lengths) of all ray paths  are 
   not plotted (default: 0)

nrskip - plot every nrskip ray traced (default: 1)

npskip - plot every npskip point of each ray traced (default: 1)

vred -  reducing  velocity  (km/s) of travel time-distance  plot;  
   observed data in the file  tx.in is assumed to be unreduced (a 
   value  of zero is  permitted for no  reduction; vred must be less 
   than 10) (default: 8)

xwndow, ywndow - the horizontal and vertical size of the graphics
   window (mm) that will over-ride a window size specified in an 
   "mx11.opt" or ".Xdefaults" file; the maximum allowable values 
   (to use the entire screen) are 350 and 265 mm, respectively  
   (defaults: if xwndow or ywndow is less than or equal to zero, 
   the size of the window specified in the "mx11.opt" or ".Xdefaults" 
   file is used)
   Note: the effect of these parameters will depend on the local 
         graphics system and machine type

dvmax, dsmax - a  warning message is written  to the screen and  the 
   to file r1.out indicating the  layers in which the  magnitude of 
   the velocity gradient vector is greater than dvmax (km/s/km) and the 
   layer boundaries having a change in slope across three successive 
   points of greater than dsmax (degrees)  (defaults: infinite, infinite)

ibcol, ifcol - background and foreground colours (defaults: 0, 1)

mcol - an array specifying the colours of the model: the layer 
   boundaries are mcol(1), the vertical boundaries are mcol(2),
   the floating reflectors are mcol(3), the smooth layer boundaries
   are mcol(4), and the velocity values are mcol(5) 
   (default: 1, 1, 1, 1, 1)

ircol - colour the ray paths according to the value of ivray for that
   particular ray group (1), according to the shot number (2), or
   according to the ray group (3) (default: 0)

itcol - colour the observed travel times according to the integer 
   code identifying each pick in the file tx.in (the 4th column) (1), 
   or according to the shot number (2); if itcol=3, the observed
   travel times are coloured as if itcol=1 and the calculated travel
   times are coloured according to ray group (invr=1 must be used)
   (default: 0)

title - title for plot (up to 80 characters long) positioned using 
   xtitle and ytitle (default: none)

xtitle, ytitle - x and y position (mm) of the plot title (default: 0, 0)

colour - an array specifying the colours of the ray paths if ircol>0
   and the observed travel times if itcol>0 
   (default: 2,3,4,5,6,8,17,27,22,7)

2) Axes parameters (AXEPAR namelist):

a) Switches  (usually 0 = off, 1 = on):

iaxlab - plot axes labels (default: 1)

itrev -  draw the  time-distance  plot with  the  time increasing  
   downward (default: 0)

b) Other axes parameters:

albht - height of axes labels (mm) (default: 2.5)

xmin, xmax - minimum and maximum distance (km) of velocity model
xmm - length of distance axis (mm)
xtmin, xtmax - minimum and maximum values (km) of tick marks
ntickx - number of intervals separated by tick marks along distance axis
ndecix - number of digits after decimal in distance axis annotation; 
   -1 for integer annotation (defaults: 0, none, 250; values for
   xtmin, xtmax, ntickx and ndecix depend on values of xmin and xmax)

zmin, zmax - minimum and maximum depth (km) of velocity model
zmm - length of depth axis (mm)
ztmin, ztmax - minimum and maximum values (km) of tick marks
ntickz - number of intervals separated by tick marks along depth axis
ndeciz - number of digits after decimal in depth axis annotation;
    -1 for integer annotation (defaults: 0, 50, 75; values for
   ztmin, ztmax, ntickz and ndeciz depend on values of zmin and zmax)

xmint, xmaxt - minimum and maximum distance (km) of time-distance plot
xmmt - length of distance axis (mm)
xtmint, xtmaxt - minimum and maximum values (km) of tick marks
ntckxt - number of intervals separated by tick marks along distance axis
ndecxt - number of digits after decimal in distance axis annotation; 
   -1 for integer annotation (defaults: xmin, xmax, xmm; values for
   xtmint, xtmaxt, ntckxt and ndecxt depend on values of xmint and xmaxt)

tmin, tmax - minimum and maximum time (s) of time-distance plot
tmm - length of time axis (mm)
ttmin, ttmax - minimum and maximum values (s) of tick marks
ntickt - number of intervals separated by tick marks along time axis
ndecit - number of digits after decimal in time axis annotation; 
   -1 for integer annotation (defaults: 0, 10, 75; values for
   ttmin, ttmax, ntickt and ndecit depend on values of tmin and tmax)

orig - lower left origin of plot is (orig,orig) mm (default: 12.5)

sep - separation (mm) between the model and travel time diagrams
   if isep=0 or 2 (default: 7.5)

3) Ray tracing parameters (TRAPAR namelist):

a) Switches (usually 0 = off, 1 = on):

ishot - an array specifying the directions rays are to be traced 
 from the shot points listed in the arrays xshot and zshot; the 
  following code is used:
   (1) 0 - no rays are traced
   (2) -1 - rays are traced to the left only
   (3) 1 - rays are traced to the right only
   (4) 2 - rays are traced to the left and right
   (default: 0)

iraysl - use the  array irayt to  select which ray  groups listed 
   in the array ray are to be traced for a particular shot point  
   (default: 0)

irayt - an array selecting  those ray groups listed  in the array 
   ray which are active for a particular shot point listed in the 
   arrays xshot and zshot.  If there are n  ray groups listed  in 
   the array ray,  then the  jth ray group  for the  ith shot is  
   referred to in  the (2n(i-1)+j)th  element of  irayt for rays  
   traced to the  left ,  and in the  (2n(i-1)+n+j)th element  of 
   irayt for rays traced to the right. You must specify values of 
   irayt for each group and for each direction regardless of  the 
   values of ishot  (default: 1)

ifast - use a Runge-Kutta routine without error control to solve
   the ray tracing equations and a look-up/interpolation routine 
   to evaluate certain trigonometric functions; with ifast=0, a
   Runge-Kutta method with error control and the intrinsic 
   trigonometric functions are used. Using ifast=1 is about 30-40%
   faster and provides essentially the same accuracy as ifast=0
   (default: 1)
   Note: ifast=1 is intended to be used for all routine modelling
         and ifast=0 only to test a final model or if ifast=1 
         obviously fails

i2pt - perform two-point ray tracing, i.e., determine the ray take-
   off angles that connect sources and observed receiver locations
   within each ray group; the receiver locations are obtained from
   the file tx.in for those picks that have the same integer code
   as specified in the array ivray for the ray group; if i2pt=2,
   only rays which reflect off the appropriate floating reflector
   specified in the array frbnd (if frbnd>0) are traced (default: 0)

iturn - an array  corresponding to the  ray groups listed  in the 
   array ray to trace  rays only to  their turning or  reflection 
   point in the search mode; if a refracted or head wave ray group 
   is to contain a reflection(s) before it turns (specified using 
   nrbnd and rbnd), then iturn=0 must be used (default: 1)

isrch - search again  for the take-off  angles of a  ray group if 
   the same ray code is listed more than once for the same shot in 
   the array ray; isrch=1 must be used if the take-off angles of 
   two or more ray  groups with the same  ray code are  different 
   because of multiple reflections and/or conversions specified by 
   nrbnd, rbnd, ncbnd,and cbnd (default: 0)

istop - stop  tracing any  ray which reflects  off a  boundary not 
   specified in the arrays ray or rbnd; if istop=2, rays are also
   stopped if they enter a layer deeper than that specified by the
   ray code in the array ray, i.e., the layer number is greater 
   than L and the ray code is L.n, where n=0, 1, 2, or 3 
   (default: 1)

idiff - continue to trace headwaves along a boundary even if the
   velocity contrast across the interface is no longer positive,
   in which case headwaves emerge parallel to the boundary (idiff=1);
   if idiff=2, initiate a headwave ray group even if there is no 
   critical point (or it is not found) to model diffractions along 
   the top of a low-velocity layer (default: 0)

ibsmth - apply  a simulation  of smooth  layer boundaries  (1) or  
   apply the simulation  and plot  the smoothed  boundaries (2);  
   ibsmth=2 has no effect if isep>1 (default: 0)

insmth - an array listing the layer boundaries for which the smooth
   layer boundary simulation is not to be applied, or only applied
   outside the model distances xminns and xmaxns, when ibsmth=1 
   or 2, (default: 0) 

imodf - use the velocity  model in the file v.in  instead of the 
   model in part (5) of the file r.in (default: 0)

b) Other ray tracing parameters:

xshot - an  array containing  the x-coordinates  (km) of the  shot 
   points (default: 0.0)

zshot - an  array containing  the z-coordinates  (km) of the  shot 
   points (default: a very small distance below the model surface)

ray -  an  array  containing the  ray  groups  to be  traced;  the  
   following code is used:
   (1) L.1 - rays which refract (turn) in the Lth layer
   (2) L.2 - rays which reflect off the bottom of the Lth layer
   (3) L.3 -  rays which  travel as  head waves along  the bottom  
   of the Lth layer
   (4) L.0  - ray  take-off angles  supplied by  the user  in the  
   arrays amin and amax

nray - an  array containing the  number of rays  to be  traced for 
   each ray group  in the  array ray  (default: 10;  however, the  
   default is the first element of nray for all ray groups if only 
   one value is specified)