PROGRAM   P O L A R P L O T
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   PROGRAM POLARPLOT IS DESIGNED FOR PLOTTING OF PARTICLE MOTION
DIAGRAMS FROM FILES LU3 GENERATED IN THE PROGRAM SYNTPL FOR DIF-
FERENT COMPONENTS OF DISPLACEMENT VECTOR. IT CAN BE ALSO USED
TO PLOT OTHER PARTICLE MOTION DIAGRAMS GENERATED ELSEWHERE BUT
STORED IN THE SAME FORM AS THOSE GENERATED IN PROGRAM SYNTPL.

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A SHORT DESCRIPTION OF THE PROGRAM
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   PARTICLE MOTION DIAGRAMS ARE PLOTTED IN A FRAME, IN WHICH THE
X- AND Y-AXES CORRESPOND TO TWO SELECTED COMPONENTS OF DISPLA-
CEMENT VECTOR. THE DIAGRAMS MAY BE PLOTTED IN A NORMALIZED FORM,
WITH MAXIMUM AMPLITUDE REACHING THE BOUNDARIES OF THE FRAME FOR
EACH RECEIVER, OR WITH REAL CHANGES OF AMPLITUDES FROM RECEIVER
TO RECEIVER. A SELECTION OF RECEIVERS AT WHICH THE PARTICLE MO-
TION DIAGRAMS ARE TO BE COMPUTED, CAN BE PERFORMED.
CALCOMP PLOTTING ROUTINES ARE REQUIRED.

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INPUT DATA
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INPUT DATA CONSIST PARTIALLY OF THE DATA GENERATED BY A PROGRAM
SYNTPL AND STORED IN A FORMATTED FORM IN TWO FILES LU3 (EACH WITH
ONE COMPONENT), AND PARTIALLY OF THE ADDITIONAL INPUT DATA CONTROL-
LING PLOTTING, INTRODUCED DIRECTLY (CARD READER, TERMINAL). THE 
Additional INPUT DATA ARE READ IN FROM STANDARD INPUT BY LIST-DIRECTED
INPUT (FREE FORMAT).


DATA STORED IN FILES LU3
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IN A FILE LU3, THE COMPUTED RAY SYNTHETIC SEISMOGRAMS FOR INDI-
VIDUAL RECEIVER POSITIONS ARE STORED, TOGETHER WITH SOME OTHER
RELEVANT IMPORTANT INFORMATION.
THE DATA IN LU3 ARE STORED IN THE FOLLOWING ORDER:
1) MTEXT                                      FORMAT(A)
   ARBITRARY ALPHANUMERIC TEXT DESCRIBING THE COMPUTATIONS. THIS
   TEXT MAY APPEAR UNDER THE PLOTS. IT WAS READ IN IN THE PROGRAM 
   SEIS.
2) MDIST,MRED,MCOMP,ITPR,VRED,RSTEP,XSOUR,DT  FORMAT(4I5,4F10.5)
   MDIST...  THE NUMBER OF RECEIVER POSITIONS.
   MRED...   MRED=0:NON REDUCED TRAVEL TIMES,
             MRED=1: REDUCED TRAVEL TIMES.
   MCOMP...  MCOMP=0: VERTICAL COMPONENT.
             MCOMP=1: RADIAL COMPONENT.
             MCOMP=2: TRANSVERSE COMPONENT.
   ITPR...   ITPR=0: RECEIVERS ALONG THE EARTH'S SURFACE.
             ITPR=1: RECEIVERS ALONG A VERTICAL PROFILE.
             ITPR.GT.100: RECEIVERS ALONG AN INTERFACE.
   VRED...   REDUCTION VELOCITY
   RSTEP...  AVERAGE DIFFERENCE BETWEEN COORDINATES OF
             NEIGHBOURING RECEIVER POSITIONS.
   XSOUR...  X-COORDINATE OF THE SOURCE.
   DT...     TIME STEP IN SYNTHETIC SEISMOGRAM.
3) XMX,SMAXIM                        FORMAT(22X,F10.5,9X,E15.9)
   XMX...    COORDINATE OF OF THE RECEIVER AT WHICH THE
             MAXIMUM AMPLITUDE 'SMAXIM' WAS RECORDED
             (X-COORDINATE FOR RECEIVERS SITUATED ALONG THE
             EARTH'S SURFACE OR ALONG AN INTERFACE, Z-COOR-
             DINATE FOR RECEIVERS SITUATED ALONG A VERTICAL
             PROFILE).
   SMAXIM... THE MAXIMUM AMPLITUDE OF ALL TRACES.
THE FOLLOWING CARDS 4,5 ARE SUCCESSIVELY REPEATED FOR ALL
RECEIVER POSITIONS:
4) XX,SMAX,TMIN,NPTS            FORMAT(F10.5,E15.9,F10.5,I5)
   XX...     COORDINATE OF THE RECEIVER (X-COORDINATE WHEN
             RECEIVERS ARE SITUATED ALONG THE EARTH'S SURFACE
             OR ALONG AN INTERFACE AND Z-COORDINATE WHEN RE-
             CEIVERS ARE SITUATED ALONG A VERTICAL PROFILE.
   SMAX...   MAXIMUM AMPLITUDE IN THE SYNTHETIC SEISMOGRAM
             AT XX.
   TMIN...   THE TIME CORRESPONDING TO THE FIRST NON-ZERO
             POINT IN THE SYNTHETIC SEISMOGRAM.
   NPTS...   NUMBER OF POINTS IN SYNTHETIC SEISMOGRAM.
5) SYNTHETIC SEISMOGRAM              FORMAT(20I4)
THE MAXIMUM LENGTH OF ONE SYNTHETIC SEISMOGRAM IS 3001 POINTS.
ONLY THE PARTS OF THE SEISMOGRAMS SITUATED BETWEEN THE FIRST
AND THE LAST NON-ZERO ARRIVAL ARE STORED. EACH SEISMOGRAM IS
STORED IN A NORMALIZED FORM, SEE THE FORMAT, WITH MAXIMUM
AMPLITUDE EQUAL 999.

ADDITIONAL INPUT DATA
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THE FOLLOWING DATA SHOULD BE INTRODUCED DIRECTLY (CARDS, TERMI-
NAL). THEY CONTROL THE PLOTTING OF SYNTHETIC SEISMOGRAMS. THE
DATA FROM LU3A AND LU3B (EACH FOR ONE COMPONENT) ARE READ IN
AFTER ALL THE ADDITIONAL INPUT DATA ARE READ IN.

1) ONE CARD
   ISHIFT,IPRINT               
   ISHIFT...THE SHIFT BETWEEN INDIVIDUAL PICTURES, IN CM.
                  DEFAULT VALUE, ISHIFT=10.
   IPRINT...CONTROLS THE PRINTOUT OF SOME DATA ON THE LINE
                  PRINTER. SEE DETAILS IN THE SECTION ON OUTPUT
                  TABLES.

2) ONE CARD, VARIOUS SWITCHES
   MCONT,MEPIC,NTICX,NTEXT        
   MCONT... MCONT=0: THE COMPUTATION TERMINATES.
            MCONT=1: A NEW PLOT OF SYNTHETIC SEISMOGRAMS
                     WILL BE MADE FROM THE SAME FILE AS THE 
                     PRECEDING PLOT.
            MCONT=-1: A NEW PLOT OF SYNTHETIC SEISMOGRAMS
                     WILL BE MADE FROM A NEW FILE. GO TO THE INPUT
                     DATA CARD NO.1.
   MEPIC... CONTROLS THE SELECTION OF RECEIVER POSITIONS
            MEPIC=0: NO SELECTION
            MEPIC=1: SELECTION APPLIED, SEE CARD NO.3
   NTICX... THE NUMBER OF MARKED INTERVALS BETWEEN TWO AD-
            JOINING TICS DENOTED BY COORDINATE VALUES ALONG
            X- AND Y-AXES.
   NTEXT... SELECTION OF THE TEXT WHICH SHOULD APPEAR UNDER
            THE PLOTS:
            NEXT=0: THE TEXT 'TEXT' STORED IN FILE LU3, IS
                    TO BE PLOTTED.
            NTEXT=1: THE TEXT 'TXT' READ FROM INPUT DATA
                    CARD NO.5, SEE BELOW, IS TO BE PLOTTED.

3) ONE CARD, SELECTION OF RECEIVER POSITIONS.
   INCLUDED ONLY WHEN MEPIC.NE.0.
   NEPIC,(IEP(I),I=1,NEPIC)                    
   NEPIC... NUMBER OF SELECTED RECEIVER POSITIONS AT WHICH
            SYNTHETIC SEISMOGRAMS ARE TO BE CONSTRUCTED.
   IEP(1),IEP(2),...,IEP(NEPIC)... SEQUENTIAL NUMBERS OF
            SELECTED RECEIVER POSITIONS (IN INCREASING
            ORDER).
NOTE: SIMILAR SELECTION CAN BE DONE ALREADY IN THE PROGRAM
SYNTPL. THE SELECTION HERE IS MADE AMONG THOSE RECEIVERS WHICH
REMAINED AFTER THE SELECTION IN SYNTPL.

4) ONE CARD, DESCRIPTION OF AXES IN THE PLOT
   XLEN,DTICX,SC,TSTART,TFIN,AMP,B1...             
   XLEN...   LENGTH OF X- AND Y-AXES (IN CM). THE MINIMUM
             AND MAXIMUM VALUES ON BOTH AXES ARE -1.0 AND
             1.0 RESPECTIVELY.
   DTICX...  THE DISTANCE BETWEEN TWO ADJOINING TICS WHICH
             ARE DENOTED BY CORRESPONDING COORDINATE VALUES
             ON BOTH AXES.
   SC...     CONTROLS THE SCALES OF TICS AND ALPHANUMERICAL
             TEXTS. FOR SC=1.0, THE TICS ARE 0.15 CM LONG
             AND COORDINATES AND TEXTS DESCRIBING THE PLOTS
             ARE 0.4 AND 0.45 CM HIGH, RESPECTIVELY. DEFAULT
             VALUE, SC=1.
   TSTART,TFIN... MINIMUM AND MAXIMUM VALUES OF THE TIME IN-
             TERVAL FOR WHICH PARTICLE MOTION DIAGRAMS ARE
             TO BE PLOTTED. THE VALUES APPEAR IN THE PLOT.
   AMP,B1... PARAMETERS OF THE AMPLITUDE SCALING OF PARTICLE
             MOTION DIAGRAMS. THEY CONTROL THE SCALING OF
             PARTICLE MOTION DIAGRAMS. DEFAULT VALUE OF B1,
             B1=1.
             DENOTE DDX=0.5*XLEN. THEN THE FOLLOWING SYSTEMS
             OF SCALING CAN BE USED:

   1) FACTOR=B1*DDX/SMAXI,
      WHEN AMP=0.
      NORMALIZATION OF MAXIMUM AMPLITUDES IN ALL DIAGRAMS:
      FOR B1=1, IN EACH FRAME THE PARTICLE MOTION DIAGRAM TOUCHES
      THE FRAME OF THE DIAGRAM WITH ITS MAXIMUM AMPLITUDE.
   2) FACTOR=B1*DDX/SMAXIM,
      WHEN AMP=-1,
      REAL CHANGES OF AMPLITUDES BETWEEN DIAGRAMS:
      FOR B1=1, THE PARTICLE MOTION DIAGRAM FOR THE RECEIVER WITH
      MAXIMUM AMPLITUDE TOUCHES THE FRAME OF THE DIAGRAM. ALL THE
      OTHER DIAGRAMS ARE WITHIN THEIR FRAMES.
   3) FACTOR=B1,
      WHEN AMP=1,
      REAL AMPLITUDES: MANUAL DETERMINATION OF THE SCALING FACTOR
      BY SPECIFYING B1.

5) ONE CARD, ALPHANUMERICAL TEXT DESCIBING THE PLOTS. IT APPEARS
   UNDER THE PLOTS WHEN NTEXT=1 IN INPUT DATA CARD NO.2.
   TXT                                    
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TERMINATION OF COMPUTATIONS
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IF MCONT=1 IN CARD NO.2, THE CARDS 2-5 CAN BE REPEATED AN ARBI-
TRARY NUMBER OF TIMES TO PLOT PARTICLE MOTION DIAGRAMS WITH DIF-
FERENT AMPLITUDE SCALING, DIFFERENT TIME INTERVALS, ETC.
IF MCONT=-1 IN CARD NO.2, THE FILES LU3A AND LU3B ARE CLOSED, AND
NUMBERS OF NEW FILES ARE READ IN FROM INPUT DATA CARD NO.1. THE
FILES ARE OPENED AND THE COMPUTATIONS PROCEED AS DESCRIBED ABOVE.
THE COMPUTATION TERMINATES WHEN MCONT=0 IN THE INPUT DATA CARD
NO.2.

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OUTPUT ON A LINE PRINTER
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ALL THE ADDITIONAL INPUT DATA ARE REPRODUCED ON THE LINE PRINTER.
THE PRINTOUT OF OTHER DATA IS CONTROLLED BY THE PARAMETER IPRINT,
SEE INPUT DATA CARD NO.1.
FOR IPRINT=0: ALSO THE DATA LU3/1,LU3/2 AND LU3/3 FROM BOTH FILES
LU3A AND LU3B ARE PRINTED.
FOR IPRINT=1: THE SAME AS FOR IPRINT=0. IN ADDITION, ONE LINE IS
PRINTED FOR EACH RECEIVER POSITION:
XX,SMAX,FACTOR,SFMAX
WHERE XX IS THE COORDINATE OF THE RECEIVER (X-COORDINATE FOR RECE-
IVERS SITUATED ALONG THE EARTH'S SURFACE OR ALONG AN INTERFACE,
Z-COORDINATE FOR RECEIVERS SITUATED ALONG A VERTICAL PROFILE),
SMAX IS THE MAXIMUM AMPLITUDE IN THE CORRESPONDING PARTICLE MOTION
DIAGRAM, FACTOR IS THE AMPLITUDE SCALING FACTOR CORRESPONDING TO
THE SPECIFIED RECEIVER, AND SFMAX IS THE MAXIMUM AMPLITUDE IN THE
PARTICLE MOTION DIAGRAM AFTER SCALING.

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