program llsl C THIS program FITS Y=A+BX C X IS THE INDEPENDENT VARIABLE ARRAY WITH N POINTS:INPUT DATA C Y IS THE DEPENDENT VARIABLE ARRAY WITH N POINTS:INPUT DATA C N IS THE NUMBER OF POINTS: INPUT DATA C R IS A two LINES ARRAY WHERE:R(1)=A,R(2)=B:OUTPUT DATA C SIG2 IS THE VARIANCE OF THE FIT:SIG2=SUM((Y OBS-Y CALC)**2)*P/(N-2): C OUTPUT DATA C CM IS THE 2X2 COVARIANCE MATRIX:OUTPUT DATA C USES SUBROUTINE SYMIN C************************************************************************ C Adapted from S. O. Kepler, this version written 16 DEC 85 C Last modified ** 16 DEC 1985 ** C************************************************************************ implicit double precision(a-h,p-z) common /x/ X(8000) common /y/ Y(8000) dimension R(2),A(2,2),B(2),CM(2,2),sigma(2) DIMENSION P(20),Q(20),RR(20) CHARACTER*20 infile pi=3.1415926536 321 write(*,322) 322 format(1x,'input file is: ', $) read(*,323) infile 323 format(a20) open(2,file=infile,status='old') c *********************************** c read in the number of data points read(2,*)N c *********************************** iii=1 write(*,521) iii 521 format(1x,'program completed phase: ', I3) write(*,522) N 522 format(1x,'N= ',i5) DO 1 I=1,2 DO 1 J=1,2 A(I,J)=0 B(I)=0 R(I)=0 CM(I,J)=0 1 CONTINUE c read header*********************************** c ***************************************** c read in data - time (x) and intensity (y) DO 325 I=1,N 325 READ(2,*) X(I),Y(I) C**325 X(I)= (X(I)-1.D0)*AINT+(AINT/2.D0) c ***************************************** iii=2 write(*,521) iii DO 2 I=1,N XI=X(I) YI=Y(I) PI=1 A(1,1)=A(1,1)+PI A(1,2)=A(1,2)+PI*XI A(2,2)=A(2,2)+PI*XI**2 B(1)=B(1)+PI*YI B(2)=B(2)+PI*YI*XI 2 CONTINUE a(2,1)=a(1,2) NN=2 C CALL SYMIN(A,NN) C SUBROUTINE SYMIN (A,NN) C C THIS SUBROUTINE INVERTS A SYMMETRIC MATRIX. C ***** INPUT DATA ***** C A = A SYMMETRIC MATRIX C NN = THE RANK OF THE MATRIX. N MUST BE LESS THAN 20. C ***** OUTPUT DATA ***** C A = THE INVERSE OF THE INPUT MATRIX C C DIMENSION A(NN,NN) C DIMENSION P(20),Q(20),R(20) 1300 FORMAT(13H0SYMIN FAILED) ZERO = 0.0 ONE = 1.0 DO 1000 M=1,NN 1000 RR(M) = ONE DO 200 M=1,NN BIG = ZERO DO 3000 L=1,NN AB = DABS(A(L,L)) IF(AB-BIG)3000,3000,4000 4000 IF(RR(L))1400,3000,1400 1400 BIG = AB K = L 3000 CONTINUE IF(BIG)6000,5000,6000 5000 WRITE (*,1300) GO TO 101 C RETURN 6000 RR(K) = ZERO Q(K) = ONE/A(K,K) P(K) = ONE A(K,K) = ZERO KM1 = K-1 IF(KM1.EQ.0) GO TO 1600 DO 7000 L=1,KM1 P(L) = A(L,K) IF(RR(L))9000,8000,9000 8000 Q(L) = A(L,K)*Q(K) GO TO 7000 9000 Q(L) = -A(L,K)*Q(K) 7000 A(L,K) = ZERO 1600 CONTINUE KP1 = K+1 IF(KP1.GT.NN) GO TO 1700 DO 1500 L=KP1,NN IF(RR(L))1200,1100,1200 1200 P(L) = A(K,L) GO TO 10000 1100 P(L) = -A(K,L) 10000 Q(L) = (-A(K,L))*Q(K) 1500 A(K,L) = ZERO 1700 CONTINUE DO 200 L=1,NN DO 200 K=L,NN 200 A(L,K) = A(L,K) + P(L)*Q(K) M = NN+1 L = NN DO 27 K=2,NN M = M-1 L = L-1 DO 27 J=1,L 27 A(M,J) = A(J,M) C RETURN C NOW THE A MATRIX IS THE INVERSE OF THE INITIAL ONE C FINDING R(I),WHERE R(1)=A,R(2)=B DO 4 I=1,2 DO 4 J=1,2 R(I)=R(I)+A(I,J)*B(J) 4 CONTINUE C FINDING SIG2 RSIG=0 DO 5 I=1,N PI=1 RSIG=RSIG+((Y(I)-R(1)-R(2)*X(I))**2)*PI 5 CONTINUE SIG2=RSIG/(N-2) C FINDIND THE CORRELATION MATRIX CM DO 6 I=1,2 DO 6 J=1,2 CM(I,J)=SIG2*A(I,J) 6 CONTINUE do 3915 i=1,2 sigma(i)=dsqrt(cm(i,i)) 3915 continue 100 format('Fitting a line y=a+bx'/,'a = ',1pe12.5,/'b = ',1pe12.5, &/'sig2= ',1pe12.3) c write header******************************* c ******************************************* 432 write(*,433) 433 format(1x,'output file name is: ', $) read(*,323) infile open(3,file=infile,status='new') write(3,99)N 99 format('npoints= ',i5) c output results write(3,100)r,sig2 write(3,110)(sigma(i),i=1,2) 110 format('siga ='1pe12.3,/'sigb ='1pe12.3) write(3,107)((cm(i,j),j=1,2),i=1,2) 107 format(31x,'Correlation Matrix'/, &29x,'a, b'/, &1x,2(2(0pg18.6,2x)/,1x)) 101 continue end