---------------------------------------------------------------------------------------PROGRAM LOGIS1
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THE LOGISTIC MAP
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THIS PROGRAM GENERATES POINTS FOR THE LOGISTIC MAP
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X(N+1) = AX(1-X)
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WHERE A IS THE BIFURCATION PARAMETER. AT THE PROMPT, SELECT 1 FOR
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THE FIRST ITERATE, 2 FOR THE SECOND ITERATE, 3 FOR THE THIRD
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ITERATE, AND 4 FOR THE FOURTH ITERATE.
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THE VALUES OF X ARE TO BE FOUND IN A FILE TITLED 'RESULT.'
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DIMENSION X(101),Y(101)
OPEN(2,FILE='RESULT',STATUS='NEW')
WRITE(*,10)
10 FORMAT(1X,'SELECT THE VALUE OF THE CONTROL PARAMETER.
',\)
READ(*,*) A
WRITE(*,20)
20 FORMAT(1X,'SELECT THE ITERATIVE MAP.
',\)
READ(*,*) N
X(1) = 0.0
GO TO (25,35,45,55) N
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FIRST ITERATE MAP
25 DO 30 I=1,100
X(I+1) = X(I)+0.01
30 Y(I) = A*X(I)*(1.0-X(I))
GO TO 65
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SECOND ITERATE MAP
35 DO 40 I=1,100
X(I+1) = X(I)+0.01
Y(I) = A*X(I)*(1.0-X(I))
40 Y(I) = A*Y(I)*(1.0-Y(I))
GO TO 65
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THIRD ITERATE MAP
45 DO 50 I=1,100
X(I+1) = X(I)+0.01
Y(I) = A*X(I)*(1.0-X(I))
Y(I) = A*Y(I)*(1.0-Y(I))
50 Y(I) = A*Y(I)*(1.0-Y(I))
GO TO 65
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FOURTH ITERATE MAP
55 DO 60 I=1,100
X(I+1) = X(I)+0.01
Y(I) = A*X(I)*(1.0-X(I))
Y(I) = A*Y(I)*(1.0-Y(I))
Y(I) = A*Y(I)*(1.0-Y(I))
60 Y(I) = A*Y(I)*(1.0-Y(I))
65 WRITE(2,70) (Y(I), I=1,101)
70 FORMAT(E14.5)
CLOSE(2)
WRITE(*,80)
80 FORMAT(1X,'PRESS RETURN TO TERMINATE.')
PAUSE
END
-------------------PROGRAM LOGIS2
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THE LOGISTIC TIME SERIES
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THIS PROGRAM GENERATES POINTS FOR THE LOGISTIC TIME SERIES X(N)
VERSUS N FROM THE LOGISTIC EQUATION
X(N+1) = AX(1-X)
WHERE A IS THE BIFURCATION PARAMETER. THE NUMBER OF POINTS TO BE
CALCUATED CANNOT BE MORE THAN 999.
THE VALUES OF X ARE TO BE FOUND IN A FILE TITLED 'RESULT.'
DIMENSION X(1000)
OPEN(2,FILE='RESULT',STATUS='NEW')
WRITE(*,10)
10 FORMAT(1X,'SELECT THE NUMBER OF POINTS TO BE CALCULATED.
',\)
READ(*,*) N
WRITE(*,20)
20 FORMAT(1X,'SELECT THE VALUE OF THE INITIAL POINT.
',\)
READ(*,*) X(1)
WRITE(*,30)
30 FORMAT(1X,'SELECT THE VALUE OF THE CONTROL PARAMETER.
',\)
READ(*,*) A
DO 50 I=1,N+1
50 X(I+1) = A*X(I)*(1.0-X(I))
WRITE(2,60) (X(I), I=1,N+1)
60 FORMAT(E14.5)
CLOSE(2)
WRITE(*,70)
70 FORMAT(1X,'PRESS RETURN TO TERMINATE.')
PAUSE
END
------------------PROGRAM LOTKA
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SOLUTION OF THE LOTKA-VOLTERRA EQUATIONS BY THE RUNGE-KUTTA METHOD
THE EQUATIONS ARE
DX/DT = X(A-BY)
DY/DT = Y(BX-C)
WHERE A,B,C ARE PARAMETERS. THE SOLUTIONS ARE ADVANCED BY A
TIME INCREMENT DT. THE PRINTOUTS OF X AND Y ARE CONTROLLED BY
THE NUMBER OF TIME INCREMENTS NUM BETWEEN WRITES TO THE OUTPUT
FILE. THIS IS SET BY THE VALUE OF M, WHERE M = 1/NUM*DT.
TOO LARGE A TIME INCREMENT WILL CAUSE ERRATIC BEHAVIOR OF THE
PROGRAM. AN INITIAL VALUE OF 0.01 IS RECOMMENDED.
WHEN ENTERING VALUES OF PARAMETERS UPON SEEING THE SCREEN PROMPT,
YOU MUST LEAVE A SPACE BETWEEN NUMBERS.
THE OUTPUT FILES ARE LABELED 'XRESULT' AND 'YRESULT.'
F1(X,Y,A,B) = X*(A-B*Y)
F2(X,Y,B,C) = Y*(B*X-C)
OPEN(2,FILE='XRESULT', STATUS='NEW')
OPEN(3,FILE='YRESULT', STATUS='NEW')
WRITE(*,10)
10 FORMAT(1X,'SELECT THE NUMBER OF POINTS TO BE CALCULATED, THE VALUE
XS OF A,B,C AND THE',/1X,'INITIAL VALUES OF X AND Y. ',\)
READ(*,*) N,A,B,C,X,Y
WRITE(*,25)
25 FORMAT(1X,'SELECT THE TIME INCREMENT AND THE VALUE OF M.
',\)
READ(*,*) DT, M
WRITE(2,40) X
WRITE(3,40) Y
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NUM IS A COUNTER FOR TIME INTERVALS BETWEEN OUTPUT WRITES
NUM = 0
DO 50 I=1,N
AK1 = F1(X,Y,A,B)*DT
AM1 = F2(X,Y,B,C)*DT
X1 = X+AK1/2.0
Y1 = Y+AM1/2.0
AK2 = F1(X1,Y1,A,B)*DT
AM2 = F2(X1,Y1,B,C)*DT
X2 = X+AK2/2.0
Y2 = Y+AM2/2.0
AK3 = F1(X2,Y2,A,B)*DT
AM3 = F2(X2,Y2,B,C)*DT
X3 = X+AK3
Y3 = Y+AM3
AK4 = F1(X3,Y3,A,B)*DT
AM4 = F2(X3,Y3,B,C)*DT
X1 = X+(AK1+2.0*AK2+2.0*AK3+AK4)/6.0
Y1 = Y+(AM1+2.0*AM2+2.0*AM3+AM4)/6.0
X = X1
Y = Y1
IF(NUM.EQ.0) GO TO 35
IF(NUM*M*DT.EQ.1) GO TO 30
GO TO 45
30 NUM = 0
35 WRITE(2,40) X
WRITE(3,40) Y
40 FORMAT(E14.5)
45 NUM = NUM + 1
50 CONTINUE
CLOSE(2)
CLOSE(3)
WRITE(*,60)
60 FORMAT(1X,'PRESS RETURN TO TERMINATE')
PAUSE
END
------------------PROGRAM MCINT
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MONTE CARLO INTEGRATION
THIS PROGRAM INTEGRATES 1/(1+X*X) USING THE RANDOM NUMBER
GENERATOR RAN2(IDUM) FROM PRESS. THE PROGRAM ASKS
FOR THE INPUT, WHICH IS THE NUMBER OF SAMPLE POINTS
(RAMDOM NUMBERS) IN THE EVALUATION
OF THE INTEGRAL.
THE OUTPUT IS TO THE SCREEN.
NOTE HOW MANY POINTS MUST BE SAMPLED TO APPROACH THE TRUE VALUE OF
2.65163.
IMPLICIT REAL*8(A-H,O-Z)
CHARACTER*3 ANS
3 WRITE (*,5)
5 FORMAT(1X,'ENTER THE NUMBER OF SAMPLE POINTS DESIRED.
READ (*,*) N
WRITE (*,7)
7 FORMAT(1X,'THE PROGRAM IS RUNNING.')
IDUM = -1
',\)
AINT = 0.0
DO 10 I=1,N
X = -4.0+8.0*RAN2(IDUM)
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THE FOLLOWING LINE IS THE FUNCTION, WHICH MAY BE CHANGED.
F = 1.0/(1.0+X*X)
AINT = AINT+F
10 CONTINUE
AINT = AINT*8.0/N
20 FORMAT(6E12.5)
WRITE (*,12) AINT
12 FORMAT(1X,'THE VALUE OF THE INTEGRAL IS',2X,E10.5)
WRITE (*,25)
25 FORMAT(1X,'DO YOU WISH TO DO ANOTHER CALCULATION? (yes OR no) ',\)
READ (*,30) ANS
30 FORMAT(A3)
IF (ANS.EQ.'yes') GO TO 3
WRITE (*,35)
35 FORMAT(1X,'PRESS RETURN TO TERMINATE')
PAUSE
END
--------------------PROGRAM POLYMER
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THIS FORTRAN PROGRAM ILLUSTRATES POLYMER FOLDING BY GENERATING A
SELF-AVOIDING RANDOM WALK. THE POLYMER MODEL IS THE BEAD-SPRING
MODEL. THE PROGRAM PROMPTS FOR THE NUMBER OF BEADS AND FOR THE
SEED VALUE FOR THE RANDOM NUMBER GENERATOR.
THE NUMBER OF BEADS CANNOT EXCEED 500.
IN SOME CASES THE POLYMER CHAIN MUST BE TERMINATED BECAUSE IT
CANNOT GROW FARTHER. SUCH CASES ARE INDICATED ON THE SCREEN AND
THE POLYMER IS DRAWN AS FAR AS IT CAN GO.
THIS IS NOT A STATISTICAL SELF-AVOIDING WALK, SINCE THE MOVES ARE
NOT ALL EQUALLY PROBABLE. IT IS INTENDED ONLY TO SHOW POLYMER
FOLDING.
THIS PROGRAM REQUIRES A RANDOM NUMBER GENERATOR SUCH AS RAN2 FOUND
IN PRESS.
THIS PROGRAM WRITES THE OUTPUT TO FILES 'RESULTX' AND 'RESULTY.'
THE OUTPUT FILES CAN BE EXPORTED TO A PLOTTING ROUTINE, OR THE
RESULTS CAN BE PLOTTED ON GRAPH PAPER.
DIMENSION IX(500),IY(500)
OPEN(2,FILE='RESULTX',STATUS='NEW')
OPEN(3,FILE='RESULTY',STATUS='NEW')
NUMBER OF BEADS IS N
WRITE(*,5)
5 FORMAT(1X,'PLEASE TYPE IN THE NUMBER OF BEADS. '\)
READ(*,*) N
WRITE(*,10)
10 FORMAT(1X,'PLEASE TYPE IN THE VALUE OF THE RANDOM NUMBER SEED.
X)
READ(*,*) IDUM
SET UP INITIAL SITES
L = 1
IX(1) = 100
IY(1) = 100
IX(2) = 100+L
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500
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IY(2) = 100
BEGIN THE RANDOM WALK
DO 150 I=3,N
A = RAN2(IDUM)
NCOUNT = 0
IF(A.LT.0.25) GO TO 115
IF(A.LT.0.5) GO TO 125
IF(A.LT.0.75) GO TO 135
NCOUNT = NCOUNT+1
IF(NCOUNT.GT.4) GO TO 500
DO 110 K=1,I-1
IF(IX(K).EQ.IX(I-1).AND.IY(K).EQ.IY(I-1)-L) GO TO 115
IX(I) = IX(I-1)
IY(I) = IY(I-1)-L
GO TO 150
NCOUNT = NCOUNT+1
IF(NCOUNT.GT.4) GO TO 500
DO 120 K=1,I-1
IF(IX(K).EQ.IX(I-1)-L.AND.IY(K).EQ.IY(I-1)) GO TO 125
IX(I) = IX(I-1)-L
IY(I) = IY(I-1)
GO TO 150
NCOUNT = NCOUNT+1
IF(NCOUNT.GT.4) GO TO 500
DO 130 K=1,I-1
IF(IX(K).EQ.IX(I-1).AND.IY(K).EQ.IY(I-1)+L) GO TO 135
IX(I) = IX(I-1)
IY(I) = IY(I-1)+L
GO TO 150
NCOUNT = NCOUNT+1
IF(NCOUNT.GT.4) GO TO 500
DO 140 K=1,I-1
IF(IX(K).EQ.IX(I-1)+L.AND.IY(K).EQ.IY(I-1)) GO TO 105
IX(I) = IX(I-1)+L
IY(I) = IY(I-1)
GO TO 150
NCOUNT > 4; CHAIN IS STUCK. REEVALUATE PREVIOUS POSITION.
MCOUNT = 0
IF(A.LT.0.25) GO TO 510
IF(A.LT.0.5) GO TO 520
IF(A.LT.0.75) GO TO 530
MCOUNT = MCOUNT+1
IF(MCOUNT.GT.4) GO TO 590
DO 505 K=1,I-1
IF(IX(K).EQ.IX(I-2).AND.IY(K).EQ.IY(I-2)-L) GO TO 510
GO TO 550
MCOUNT = MCOUNT+1
IF(MCOUNT.GT.4) GO TO 590
DO 515 K=1,I-1
IF(IX(K).EQ.IX(I-2)-L.AND.IY(K).EQ.IY(I-2)) GO TO 520
GO TO 560
MCOUNT = MCOUNT+1
IF(MCOUNT.GT.4) GO TO 590
DO 525 K=1,I-1
IF(IX(K).EQ.IX(I-2).AND.IY(K).EQ.IY(I-2)+L) GO TO 530
GO TO 570
MCOUNT = MCOUNT+1
IF(MCOUNT.GT.4) GO TO 590
DO 535 K=1,I-1
535 IF(IX(K).EQ.IX(I-2)+L.AND.IY(K).EQ.IY(I-2)) GO TO 540
GO TO 580
550 IX(I-1) = IX(I-2)
IY(I-1) = IY(I-2)-L
GO TO 102
560 IX(I-1) = IX(I-2)-L
IY(I-1) = IY(I-2)
GO TO 102
570 IX(I-1) = IX(I-2)
IY(I-1) = IY(I-2)+L
GO TO 102
580 IX(I-1) = IX(I-2)+L
IY(I-1) = IY(I-2)
GO TO 102
590 WRITE(*,595)
595 FORMAT('CHAIN GROWTH TERMINATED')
GO TO 205
150 CONTINUE
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WRITE FINAL CONFIGURATION TO FILES "RESULTX" AND "RESULTY"
205 WRITE(2,645) (IX(I),I=1,N)
WRITE(3,645) (IY(I),I=1,N)
645 FORMAT(I5)
CLOSE(2)
CLOSE(3)
WRITE(*,650)
650 FORMAT(1X,'PRESS RETURN TO TERMINATE')
PAUSE
END
-------------------PROGRAM PWRSPR
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POWER SPECTRUM
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THE INPUT FOR THE POWER SPECTRUM CONSISTS OF A TIME SERIES,
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EITHER CALCULATED OR MEASURED IN AN EXPERIMENT. THESE DATA
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ARE IN A FILE NAMED 'DATA.' THE NUMBER OF DATA POINTS
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OF THE TIME SERIES MUST BE PROVIDED ACCORDING TO THE PROMPT.
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THE OUTPUT IS THE POWER SPECTRUM IN A FILE NAMED 'RESULT.'
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THERE IS NO WINDOW PROVIDED FOR THE FOURIER TRANSFORM, SO THERE
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MAY BE LEAKAGE IN THE TRANSFORM AND THE POWER SPECTRUM.
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ALSO, CONSTANT COEFFICIENTS SUCH AS THE TIME INCREMENT AND THE
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TOTAL TIME HAVE BEEN OMITTED.
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THE OUTPUT DATA MAY BE EXPORTED TO YOUR FAVORITE GRAPHICS PROGRAM.
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IMPLICIT REAL*8(A-H,O-Z)
DIMENSION X(2700),Y(2700),YIMAG(2700)
DATA PI/3.141593/
OPEN(2,FILE='DATA',STATUS='OLD',FORM='FORMATTED')
OPEN(3,FILE='RESULT',STATUS='NEW',FORM='FORMATTED')
WRITE(*,10)
10 FORMAT(1X,'SELECT THE NUMBER OF POINTS FOR THE POWER SPECTRUM. TH
XIS SHOULD AGREE WITH',/1X,'THE OUTPUT (LESS ONE) FROM THE TIME SER
XIES. ',\)
READ(*,*) N
READ (2,20) (X(I), I=1,N)
20 FORMAT (E14.5)
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FOURIER TRANSFORM
DO 50 J=1,N
Y(J) = 0.0
YIMAG(J) = 0.0
DO 40 I=1,N
Y(J) = X(I)*COS(2.0*PI*J*(I-1)/(N+1))+Y(J)
40 YIMAG(J) = X(I)*SIN(2.0*PI*J*(I-1)/(N+1))+YIMAG(J)
50 CONTINUE
DO 60 J=1,N
Y(J) = Y(J)*Y(J)
YIMAG(J) = YIMAG(J)*YIMAG(J)
60 Y(J) = Y(J)+YIMAG(J)
WRITE(3,20) (Y(J), J=1,N)
CLOSE(2)
CLOSE(3)
WRITE(*,70)
70 FORMAT(1X,'PRESS RETURN TO TERMINATE')
PAUSE
END
------------------PROGRAM REVCA
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REVERSIBLE CELLULAR AUTOMATA
THIS PROGRAM CALCULATES ONE-DIMENSIONAL REVERSIBLE
CELLULAR AUTOMATA USING THE NEIGHBOR-THREE RULES OF
[WOLFRAM, 1983]. THE INPUT CONSISTS OF THE NUMBER OF
SITES (CELLS) N IN THE CA PLUS TWO TO TAKE INTO ACCOUNT THE ENDS
FOR CYCLIC BOUNDARY CONDITIONS, THE NUMBER OF TIME VALUES
(INCLUDING TIME ZERO) NT, AND THE ORIGINAL CONFIGURATION IX(NT,N)
COMPRISED OF 1 OR 0. THE VALUES OF N, NT, AND THE INITIAL
CONFIGURATION MUST BE ENTERED IN A FILE LABELED 'INPUT.'
SEE THE PROGRAM FOR THE FORMAT OF THE INPUT DATA.
THE CA RULES IN THE PROGRAM MUST BE CHANGED FOR EACH NEW CA AND
THE PROGRAM MUST BE RECOMPILED FOR EACH NEW CA.
THE VALUE OF N MUST NOT EXCEED 100 AND THE VALUE OF NT MUST NOT
EXCEED 500.
THE CA APPEAR DIRECTLY ON THE SCREEN.
IMPLICIT REAL*8(A-H,O-V), INTEGER(I-N)
DIMENSION IX(500,100),IY(500,100)
OPEN(2, FILE='INPUT',STATUS='OLD')
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READ IN THE NUMBER OF CELLS (+2) AND THE NUMBER OF TIME STEPS
READ(2,*) N,NT
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READ IN THE INITIAL CONFIGURATION.
READ(2,*) (IX(1,J), J=1,N)
DO 20 J=2,N-1
C*****THE CA RULES MUST BE SPECIFIED BELOW. THE NEIGHBORHOODS ARE
C*****LABELED. IF DESIRED, THE CA NUMBER CAN BE RECORDED IN THE
C*****NEXT STATEMENT.
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CELLULAR AUTOMATA RULES FOR CA 126
IF(IX(1,J).EQ.1) GO TO 15
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NEIGHBORHOOD 101
IF(IX(1,J-1).EQ.1.AND.IX(1,J+1).EQ.1) IX(1+1,J) = 1
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NEIGHBORHOOD 100
IF(IX(1,J-1).EQ.1.AND.IX(1,J+1).EQ.0) IX(1+1,J) = 1
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NEIGHBORHOOD 001
IF(IX(1,J-1).EQ.0.AND.IX(1,J+1).EQ.1) IX(1+1,J) = 1
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NEIGHBORHOOD 000
IF(IX(1,J-1).EQ.0.AND.IX(1,J+1).EQ.0) IX(1+1,J) = 0
GO TO 20
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NEIGHBORHOOD 111
15 IF(IX(1,J-1).EQ.1.AND.IX(1,J+1).EQ.1) IX(1+1,J) = 0
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NEIGHBORHOOD 110
IF(IX(1,J-1).EQ.1.AND.IX(1,J+1).EQ.0) IX(1+1,J) = 1
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NEIGHBORHOOD 011
IF(IX(1,J-1).EQ.0.AND.IX(1,J+1).EQ.1) IX(1+1,J) = 1
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NEIGHBORHOOD 010
IF(IX(1,J-1).EQ.0.AND.IX(1,J+1).EQ.0) IX(1+1,J) = 1
20 CONTINUE
IX(1+1,1) = IX(1+1,N-1)
IX(1+1,N) = IX(1+1,2)
DO 120 I=2,NT-1
DO 118 J=2,N-1
C*****THE CA RULES MUST BE SPECIFIED BELOW. THE NEIGHBORHOODS ARE
C*****LABELED. IF DESIRED, THE CA NUMBER CAN BE RECORDED IN THE
C*****NEXT STATEMENT.
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CELLULAR AUTOMATA RULES FOR CA 126
IF(IX(I,J).EQ.1) GO TO 108
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NEIGHBORHOOD 101
IF(IX(I,J-1).EQ.1.AND.IX(I,J+1).EQ.1) IY(I+1,J) = 1
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NEIGHBORHOOD 100
IF(IX(I,J-1).EQ.1.AND.IX(I,J+1).EQ.0) IY(I+1,J) = 1
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NEIGHBORHOOD 001
IF(IX(I,J-1).EQ.0.AND.IX(I,J+1).EQ.1) IY(I+1,J) = 1
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NEIGHBORHOOD 000
IF(IX(I,J-1).EQ.0.AND.IX(I,J+1).EQ.0) IY(I+1,J) = 0
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ADD LINE NT-2 MOD 2 (DO NOT CHANGE THE NEXT FOUR STATEMENTS.)
IF(IX(I-1,J).EQ.0.AND.IY(I+1,J).EQ.0) IX(I+1,J) = 0
IF(IX(I-1,J).EQ.0.AND.IY(I+1,J).EQ.1) IX(I+1,J) = 1
IF(IX(I-1,J).EQ.1.AND.IY(I+1,J).EQ.0) IX(I+1,J) = 1
IF(IX(I-1,J).EQ.1.AND.IY(I+1,J).EQ.1) IX(I+1,J) = 0
GO TO 118
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NEIGHBORHOOD 111
108 IF(IX(I,J-1).EQ.1.AND.IX(I,J+1).EQ.1) IY(I+1,J) = 0
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NEIGHBORHOOD 110
IF(IX(I,J-1).EQ.1.AND.IX(I,J+1).EQ.0) IY(I+1,J) = 1
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NEIGHBORHOOD 011
IF(IX(I,J-1).EQ.0.AND.IX(I,J+1).EQ.1) IY(I+1,J) = 1
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NEIGHBORHOOD 010
IF(IX(I,J-1).EQ.0.AND.IX(I,J+1).EQ.0) IY(I+1,J) = 1
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ADD LINE NT-2 MOD 2 (DO NOT CHANGE THE NEXT FOUR STATEMENTS.)
IF(IX(I-1,J).EQ.0.AND.IY(I+1,J).EQ.0) IX(I+1,J) = 0
IF(IX(I-1,J).EQ.0.AND.IY(I+1,J).EQ.1) IX(I+1,J) = 1
IF(IX(I-1,J).EQ.1.AND.IY(I+1,J).EQ.0) IX(I+1,J) = 1
IF(IX(I-1,J).EQ.1.AND.IY(I+1,J).EQ.1) IX(I+1,J) = 0
118 CONTINUE
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ADD CYCLIC BOUNDARY CONDITIONS
IX(I+1,1) = IX(I+1,N-1)
IX(I+1,N) = IX(I+1,2)
120 CONTINUE
DO 125 I=1,NT
DO 127 J=1,N
IF(IX(I,J).EQ.0) GO TO 128
WRITE(*,130)
130 FORMAT(''\)
GOTO 127
128 WRITE(*,129)
129 FORMAT(' '\)
127 CONTINUE
WRITE(*,126)
126 FORMAT(' ')
125 CONTINUE
CLOSE(2)
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SCREEN REMARK
WRITE(*,160)
160 FORMAT(1X,'PRESS RETURN TO TERMINATE')
PAUSE
END
------------------PROGRAM SQRCA
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SQUARE CELLULAR AUTOMATON
THIS PROGRAM FOLLOWS THE EVOLUTION OF FIVE-NEIGHBOR, SUM MODULO 2
RULE FOR CA 614. CYCLIC BOUNDARY CONDITIONS ARE USED. THE (1,1),
(1,N), (N,1), AND (N,N) ELEMENTS ARE NEVER USED AND CAN BE READ IN
AS 0.
THE INPUT IS IN A FILE LABELED 'INPUT' AND CONTAINS THE SIZE OF
THE CA, THE NUMBER OF TIME STEPS, AND THE INITIAL CONFIGURATION.
SEE THE PROGRAM FOR THE FORMAT OF THE INPUT DATA.
THE OUTPUT IS DIRECTLY TO THE SCREEN.
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IMPLICIT REAL*8(A-H,O-V), INTEGER(I-N)
DIMENSION IX(100,100),IY(100,100)
OPEN(2, FILE='INPUT',STATUS='OLD')
READ IN THE SIZE OF THE CA (+2) AND THE NUMBER OF TIME STEPS (NT)
READ(2,*) N,NT
READ IN THE INITIAL CONFIGURATION
THE ARRAY IS READ IN WITH THE COLUMN INDEX INCREASING MOST RAPIDLY
READ(2,*) ((IX(I,J), J=1,N), I=1,N)
DO 100 IT=1,NT
DO 30 I=2,N-1
DO 20 J=2,N-1
IY(I,J) = IX(I,J-1)+IX(I,J)+IX(I,J+1)+IX(I-1,J)+IX(I+1,J)
IY(I,J) = MOD(IY(I,J),2)
CONTINUE
SET UP NEW CONFIGURATION
DO 60 I=2,N-1
DO 50 J=2,N-1
IX(I,J) = IY(I,J)
CONTINUE
IMPOSE CYCLIC BOUNDARY CONDITIONS
DO 80 I=2,N-1
IX(I,1) = IX(I,N-1)
IX(I,N) = IX(I,2)
DO 90 J=2,N-1
IX(1,J) = IX(N-1,J)
IX(N,J) = IX(2,J)
CONTINUE
PRINT OUT IN A SQUARE ARRAY
DO 140 I=2,N-1
DO 110 J=2,N-1
IF(IX(I,J).EQ.0) GO TO 120
WRITE(*,115)
115 FORMAT(''\)
GOTO 110
120 WRITE(*,125)
125 FORMAT(' '\)
110 CONTINUE
WRITE(*,130)
130 FORMAT(' ')
140 CONTINUE
CLOSE(2)
C
SCREEN REMARK
WRITE(*,160)
160 FORMAT(1X,'PRESS RETURN TO TERMINATE')
PAUSE
END