*************************************** Description of the program V E L P L *************************************** Program VELPL is designed for plotting plane sections of slowness, phase velocity and group velocity surfaces in an arbitrary anisotropic medium. File LU3 generated in the program ANRAY contains data for the plots. Description of input and output files ------------------------------------- Main input data are read from the standard input by list-directed input (free format) and consist of a single line containing following data: 'LIN' 'LOU' 'LU3'/ Here: 'LIN' is the name of the input data file LIN. 'LOU' is the name of the output log file LOU. 'LU3' is the name of the input data file LU3, generated by program ANRAY. / is a slash recomended in batch and script files to enable future extensions. Defaults: 'LIN'='velpl.dat' 'LOU'='velpl.out' 'LU3'='lu3.dat' Example of the main input data: 'velpl.vel' / Input data consist partially of the data obtained in the program ANRAY, which are stored in the formated form in the file LU3, and partially of the additional input data read by list-directed input (free format), specified by the user in the file LIN. Output data describing the computations are stored in the file LOU. The program generates a postscript file with the desired plot. Description of the content of the file LU3 ----------------------------------------- File LU3 contains data necessary for construction of sections of slowness surfaces, phase velocity and group velocity surfaces generated in the program ANRAY. The data are stored in LU3 in the following formatted form: 1) ITYPE,NPAR,INUM FORMAT(16I5) ITYPE... ITYPE=1: qS1 wave. ITYPE=2: qS2 wave. ITYPE=3: qP wave. NPAR... NPAR=1: plot of section of slowness surface. NPAR=2: plot of section of phase velocity surface. NPAR=3: plot of section of group velocity surface. INUM... number of samples in the plot. 2) DDELTA,XX(I),YY(I),ZZ(I) FORMAT(4E15.5) DDELTA... angle (in radians), for which the vector (XX,YY,ZZ) is calculated. XX(I),YY(I),ZZ(I)... x,y and z components of the slowness vector (if NPAR=1), phase velocity vector (if NPAR=2) or group velocity vector (if NPAR=3) for the angle DDELTA. Maximum points: 300. The line 2 is repeated for all the angles of all the three waves. The additional input data in the file LIN ----------------------------------------- These data are specified by the user. They control plotting. 1) TEXT Arbitrary alphanumerical text which is shown below the plots. Default 'VELPL'. 2) IPLOT,IPRINT,SC,PSTEXT IPLOT... controls the form of the resulting plot. IPLOT.GE.0: polar plot of a section of a surface. IPLOT.LT.0: plot of one quadrant of a section of a surface in a rectangular frame (horizontal axis: angle (in degrees); vertical axis: velocity (slowness). IPRINT... controls the printout into the file LOU and the type of the name of the postscript file with a plot. IPRINT.GE.0... automatic generation of postscript file names: plot00.ps, plot01.ps, etc. IPRINT.LT.0... postscript file name specified by the user, see PSTEXT. IPRINT=0... print of input data only (default value). IABS(IPR)=1... print of velocity (slowness) vectors for each specified angle. SC... scaling factor, controls the scales of tics and alphanumeric texts. For SC=1., the tics are 0.15 cm long and coordinates and text describing the plot are 0.4 and 0.45 cm high, respectively. Deafult SC=1. PSTEXT... the name of the postscript file specified by the user; it is used only if IPRINT.LT.0. 3) If IPLOT.GE.0, then: XM,XLEN,DTICX,YM,YLEN,DTICY XM... horizontal halflength of the frame, in which the section of a surface is to be displayed, in user length units, e.g. km. XLEN... length of the horizontal axis, in cm. DTICX... the distance between two neighbouring tics on the horizontal axis. The tics are denoted by the corresponding coordinate values (in the user length units). DTICX.GT.0.: Tic marks starting from -XM and appearing at the subsequent points -XM+DTICX, -XM+2.0*DTICX,... DTICX.LT.0.: Tic marks start and continue to be plotted from the first integer multiple of ABS(DTICX) greater than -XM. YM,YLEN,DTICY... the same for the vertical axis. If IPLOT.LT.0, then: XLEN,DTICX,YMIN,YMAX,YLEN,DTICY XLEN... length of the horizontal axis, in cm. DTICX... the distance between two neighbouring tics on the horizontal axis. The tics are denoted by the corresponding coordinate values (in the user length units). DTICX.GT.0.: Tic marks starting from 0. and appearing at the subsequent points DTICX, 2.0*DTICX,... DTICX.LT.0.: Tic marks start and continue to be plotted from the first integer multiple of ABS(DTICX) greater than 0.. YMIN,YMAX... the minimum and maximum values along the vertical axis (in velocity (slowness) units). YLEN... length of the vertical axis, in cm. DTICY... the distance between two neighbouring tics on the vertical axis. The tics are denoted by the corresponding coordinate values (in velocity (slowness) units). DTICY.GT.0.: Tic marks starting from YMIN and appearing at the subsequent points YMIN+DTICY, YMIN+2.0*DTICY,... DTICY.LT.0.: Tic marks start and continue to be plotted from the first integer multiple of ABS(DTICY) greater than YMIN. 4) NTICX,NTICY,NDX,NDY NTICX... the number of marked intervals on the horizontal axis between two neighbouring tics with corresponding coordinate values. Default NTICX=1. NTICY... the same as NTICX, but for the vertical axis. Default NTICY=1. NDX,NDY,... control the precision of numbers describing the coordinate axes in the plots. NDX corresponds to the horizontal axis, NDY to vertical axis. ND.GT.0: The number of digits to the right of the decimal point. ND=0: Only integer portions of the numbers with decimal points. Default value ND.LT.0: Integers. Example of data LIN Termination of computations --------------------------- The computation terminates when the sections of the three waves propagating in an anisotropic medium are plotted. Output to the file LOU ---------------------- The file contains a copy of the input data followed by lines containing the following information: DDELTA,V,XV,YV,ZV. DDELTA... the angle (in radians), for which are the following values calculated. V... value of the slowness (NPAR=1), phase velocity (NPAR=2) or group velocity (NPAR=3). XV,YV,ZV... components of the slowness vector, phase velocity or group velocity vector.