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ModWeimer.f
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ModWeimer.f
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module EIE_ModWeimer
contains
c
c The code has been made to implicit real*8 by Mei-Ching Fok on
c Jan. 30, 2002
************************ Copyright 1996,2001 Dan Weimer/MRC ***********************
*
* Subroutines to calculate the electric potentials from the "Weimer 2K" model of
* the polar cap ionospheric electric potentials described in the publication:
* Weimer, D. R., An improved model of ionospheric electric potentials including
* substorm perturbations and application to the Geospace Environment Modeling
* November 24, 1996 event, Journal of Geophysical Research, Vol. 106, p. 407, 2001.
*
* To use, first call procedure SETMODEL00 with the specified input parameters:
* angle: IMF Y-Z clock angle in degrees, 0=northward, 180=southward
* Bt: Magnitude of IMF in Y-Z plane in nT
* Tilt: dipole tilt angle in degrees.
* SWVel: solar wind velocity in km/sec
* SWDen: solar wind density in #/cc
* ALindex: (optional) AL index in nT
*
* The function EPOTVAL00(gLAT,gMLT) can then be used repeatively to get the
* electric potential in kV at the desired location.
* Input coordinates assume use of 'altitude adjusted' corrected geomagnetic
* coordinates for R=1, also refered to as AACGM0.
*
* The function BOUNDARYLAT00(gMLT) can be used to get the latitude of the boundary
* where the potential goes to zero. This boundary is a function of MLT, and
* varies with the SETMODEL00 parameters. The potential is zero everywhere below
* this boundary.
*
* Two data files are provided:
* 'w2klittle.dat' for LITTLE_ENDIAN machines.
* 'w2kbig.dat' for BIG_ENDIAN machines.
* You must copy or rename the correct one to the file 'w2k.dat'
*
* This code is protected by copyright and is distributed
* for research or educational use only.
* Commerical use without written permission from Dan Weimer/MRC is prohibited.
*
************************ Copyright 1996,2001 Dan Weimer/MRC ***********************
SUBROUTINE DLEGENDRE00(x,lmax,mmax,Plm,dPlm)
* compute Double Precision Associate Legendre Function P_l^m(x), as well as optional
* derivatives, for all L up to lmax and all M up to mmax.
* Returns results in array Plm, which should be dimensioned as double precision
* with size (0:10,0:10).
* If the first element of dPlm is not zero, then the first derivatives are also
* computed, and put into array dPlm. To skip the derivatives it is only necessary
* to put a scalar 0.D0 in the dPlm parameter. Otherwise, dPlm should also be a
* double precision array of size (0:10,0:10).
* The recursion formulas keep a count of the exponents of the factor SQRT(1-x^2)
* in both the numerator and denominator, which may cancel each other in the
* final evaluation, particularly with the derivatives. This prevents infinities
* at x=-1 or +1.
* If X is out of range ( abs(x)>1 ) then value is returns as if x=1.
implicit real*8 (a-h,o-z)
real*8 x,xx,Plm(0:10,0:10),P(0:10,0:10,0:1),fact,sfact
real*8 dPlm(0:10,0:10),dP(0:10,0:10,0:2),anum,term
LOGICAL DodPlm
DodPlm=dPlm(0,0) .NE. 0.d0
DO l=0,lmax
DO m=0,mmax
Plm(l,m)=0.D0
P(l,m,0)=0.D0
P(l,m,1)=0.D0
ENDDO
ENDDO
IF(lmax .LT. 0 .OR. mmax .LT. 0 .OR. mmax .GT. lmax )THEN
Print *,'Bad arguments to DLegendre00'
RETURN
ENDIF
* Copy x to xx, and make sure it is in range of -1. to +1.
xx=MIN(x,1.D0)
xx=MAX(xx,-1.D0)
P(0,0,1)=1.D0
IF(lmax.GT.0) P(1,0,1)=xx
IF(lmax.GT.1)THEN
DO L=2,lmax
P(L,0,1)=( (2.D0*L-1)*xx*P(L-1,0,1) - (L-1)*P(L-2,0,1) ) / L
ENDDO
ENDIF
fact=1.D0-xx**2
sfact=DSQRT(fact)
IF(mmax .GT. 0)THEN
DO M=1,mmax
DO L=M,lmax
L2=MAX( L-2 , 0 )
P(L,M,1)= P(L2,M,1) -(2*L-1)*P(L-1,M-1,0)*fact
P(L,M,0)= P(L2,M,0) -(2*L-1)*P(L-1,M-1,1)
ENDDO
ENDDO
ENDIF
IF(DodPlm)Then !do derivatives
* First zero arrays
DO l=0,lmax
DO m=0,mmax
dPlm(l,m)=0.D0
dP(l,m,0)=0.D0
dP(l,m,1)=0.D0
dP(l,m,2)=0.D0
ENDDO
ENDDO
IF(lmax .GT. 0) dP(1,0,1)=1.D0
IF(lmax .GT. 1)THEN
DO L=2,lmax
dP(L,0,1)=( (2*L-1)*P(L-1,0,1) +
$ (2*L-1)*xx*dP(L-1,0,1) -
$ (L-1)*dP(L-2,0,1) ) / L
ENDDO
ENDIF
IF(mmax .GT. 0)THEN
DO M=1,mmax
DO L=M,lmax
L2=MAX( L-2 , 0 )
dP(L,M,1)= dP(L2,M,1) - (2*L-1)*fact*dP(L-1,M-1,0) -
$ (2*L-1)*dP(L-1,M-1,2) + (2*L-1)*xx*P(L-1,M-1,0)
dP(L,M,0)= dP(L2,M,0) - (2*L-1)*dP(L-1,M-1,1)
dP(L,M,2)=dP(L2,M,2) +(2*L-1)*xx*P(L-1,M-1,1)
ENDDO
ENDDO
ENDIF
DO L=0,lmax
mlimit=MIN(mmax,L)
DO M=0,mlimit
* Prevent a divide by zero
anum=dP(L,M,2) !numerator
IF(sfact.NE.0.)Then !denominator is OK
term=anum/sfact
ELSE !denominator is zero
IF(DABS(anum).LT.1.D-7)THEN
term=0.D0 !return 0 in cases where numerator is near zero
ELSE !return nearly infinity with same sign as numerator
term=DSIGN(1.D36,anum)
ENDIF
ENDIF
dPlm(L,M)=dP(L,M,1) + dP(L,M,0)*sfact + term
ENDDO
ENDDO
ENDIF !End doing derivative
DO L=0,lmax
mlimit=MIN(mmax,L)
DO M=0,mlimit
Plm(L,M)=P(L,M,1) + P(L,M,0)*sfact
ENDDO
ENDDO
RETURN
END SUBROUTINE DLEGENDRE00
************************ Copyright 1996,2001 Dan Weimer/MRC ***********************
* FUNCTION FSVal00(omega,MaxN,FSC)
*
** Fourier Series Value
*
** Return value of Sine/Cosine Fourier series for N terms up to MaxN
*
** at angle omega, given the F.S. coeficients in array FSC
*
* implicit real*8 (a-h,o-z)
* REAL*8 omega,FSC(0:1,0:*)
*
* INTEGER MaxN,n
*
* REAL*8 Y,theta
*
* Y=0.
*
* DO n=0,MaxN
*
* theta=omega*n
*
* Y=Y + FSC(0,n)*COS(theta) + FSC(1,n)*SIN(theta)
*
* ENDDO
*
* FSVal=Y
*
* RETURN
*
* END
************************ Copyright 1996,2001 Dan Weimer/MRC ***********************
SUBROUTINE SetModel00(angle,Bt,Tilt,SWVel,SWDen,ALindex,UseAL)
*
* Calculate the complete set of spherical harmonic coeficients,
* given an aribitrary IMF angle (degrees from northward toward +Y),
* magnitude Bt (nT), dipole tilt angle (degrees),
* solar wind velocity (km/sec), SWDen (#/cc),
* ALindex (nT), and Logical flag to use optional AL index.
*
* Sets the value of Coef and Boundfit in the common block SetW00Coef.
*
implicit real*8 (a-h,o-z)
REAL*8 angle,Bt,Tilt,SWVel,SWDen,ALindex
LOGICAL First,UseAL
DATA First/.TRUE./
SAVE First
INTEGER unit
CHARACTER*15 cfile
CHARACTER*30 Copyright
PARAMETER (MJ=3,ML=4,MM=3,MN=2,MO=2)
integer :: iMJ,iMO,iML,iMM,iMN
REAL*4 CS( 0:MJ, 0:1 , 0:MO, 0:1 , 0:ML, 0:MM)
REAL*4 BCS( 0:MJ, 0:1 , 0:MO, 0:1 , 0:MN)
REAL*4 SS( 0:1 , 0:1 , 0:MO, 0:1 , 0:ML, 0:MM)
REAL*4 BSS( 0:1 , 0:1 , 0:MO, 0:1 , 0:MN)
REAL*8 XA(0:MJ),XB(0:MJ),FSC(0:1,0:4),PSS(0:1)
REAL*8 Coef(0:1,0:5,0:5),BoundFit(0:1,0:5),pi
real*8 dpi
INTEGER*4 i,j,k,l,m,n,o
INTEGER*4 maxj,MaxL,MaxM,MaxN,MaxO
COMMON /EIE_AllW00Coefs/MaxJ,MaxO,CS,BCS,SS,BSS
COMMON /EIE_SetW00Coef/Coef,BoundFit,pi,dpi,MaxL,MaxM,MaxN
If(First)Then
cfile='EIE/w2k.dat' !make sure correct ENDIAN type file is used.
unit=9
c OPEN(UNIT=unit,FILE=cfile,STATUS='OLD',form='UNFORMATTED')
OPEN(UNIT=unit,FILE=cfile,STATUS='old',form='FORMATTED')
READ(unit,*) Copyright
c PRINT *,Copyright
read(unit,*) Maxj,MaxL,MaxM,MaxN,MaxO
If(maxj.NE.MJ .OR. MaxL.NE.ML .OR. MaxM.NE.MM .OR.
$ MaxN.NE.MN .OR. MaxO.NE.MO)Then
PRINT *,'Data File Error'
STOP !Data file did not match sixe expected for arrays
Endif
do iMJ=0,MJ
do i=0,1
do iMO=0,MO
do j=0,1
do iML=0,ML
do iMM=0,MM
read(unit,*) CS( iMJ, i , iMO, j , iML, iMM)
enddo
enddo
enddo
enddo
enddo
enddo
do iMJ=0,MJ
do i=0,1
do iMO=0,MO
do j=0,1
do iMN=0,MN
read(unit,*) BCS( iMJ, i , iMO, j , iMN)
enddo
enddo
enddo
enddo
enddo
do i=0,1
do j=0,1
do iMO=0,MO
do k=0,1
do iML=0,ML
do iMM=0,MM
read(unit,*) SS( i , j , iMO, k , iML, iMM)
enddo
enddo
enddo
enddo
enddo
enddo
do i=0,1
do j=0,1
do iMO = 0,MO
do k=0,1
do iMN=0,MN
read(unit,*) BSS( i , j , iMO, k , iMN)
enddo
enddo
enddo
enddo
enddo
CLOSE(unit)
pi=2.*ASIN(1.)
dpi=2.D0*DASIN(1.D0)
First=.FALSE.
Endif
SinTilt=SIN(Tilt)
omega=angle*pi/180.
XA(0)=1.
XA(1)=Bt**(2./3.) *SWvel
XA(2)=SinTilt
XA(3)=SWvel**2 *SWDen
XB(0)=1.
XB(1)=Bt
XB(2)=SinTilt
XB(3)=SWvel**2 *SWDen
DO l=0,MaxL
mlimit=MIN(l,MaxM)
DO m=0,mlimit
klimit=MIN(m,1)
DO k=0,klimit
acoef=0. !rezero for summation
DO j=0,MaxJ
DO o=0,MaxO
DO i=0,1
FSC(i,o)=CS(j,i,o,k,l,m)
ENDDO
ENDDO
acoef=acoef+ XA(j)*FSVAL(omega,MaxO,fsc)
ENDDO
IF(UseAL)THEN
DO j=0,1
DO o=0,MaxO
DO i=0,1
FSC(i,o)=SS(j,i,o,k,l,m)
ENDDO
ENDDO
PSS(j)=FSVAL(omega,MaxO,fsc)
ENDDO
acoef=acoef + PSS(0) + PSS(1)*ALindex
ENDIF
Coef(k,l,m)=acoef
ENDDO
ENDDO
ENDDO
DO n=0,MaxN
klimit=MIN(n,1)
DO k=0,klimit
acoef=0. !rezero for summation
DO j=0,MaxJ
DO o=0,MaxO
DO i=0,1
FSC(i,o)=BCS(j,i,o,k,n)
ENDDO
ENDDO
acoef=acoef+ XB(j)*FSVAL(omega,MaxO,fsc)
ENDDO
IF(UseAL)THEN
DO j=0,1
DO o=0,MaxO
DO i=0,1
FSC(i,o)=BSS(j,i,o,k,n)
ENDDO
ENDDO
PSS(j)=FSVAL(omega,MaxO,fsc)
ENDDO
acoef=acoef + PSS(0) + PSS(1)*ALindex
ENDIF
BoundFit(k,n)=acoef
ENDDO
ENDDO
RETURN
END SUBROUTINE SetModel00
****************** Copyright 1996, 2001, Dan Weimer/MRC ***********************
FUNCTION BoundaryLat00(gmlt)
implicit real*8 (a-h,o-z)
REAL*8 gmlt
REAL*8 Coef(0:1,0:5,0:5),BoundFit(0:1,0:5),pi
real*8 dpi
integer*4 MaxL,MaxM,MaxN
COMMON /EIE_SetW00Coef/Coef,BoundFit,pi,dpi,MaxL,MaxM,MaxN
BoundaryLat00 = FSVal(gmlt*pi/12.,MaxN,BoundFit)
RETURN
END FUNCTION BoundaryLat00
****************** Copyright 1996, 2001, Dan Weimer/MRC ***********************
FUNCTION EpotVal00(gLAT,gMLT)
* Return the value of the electric potential in kV at
* corrected geomagnetic coordinates gLAT (degrees) and gMLT (hours).
*
* Must first call SetModel00 to set up the model coeficients for
* the desired values of Bt, IMF clock angle, Dipole tilt angle, SW Vel,
* number density, and (optional) AL index.
*
implicit real*8 (a-h,o-z)
REAL*8 gLAT,gMLT
real*8 Phi,Z,O,x,ct,Phim
real*8 Plm(0:10,0:10),OPlm(0:10,0:10)
real*8 dPlm(0:10,0:10)
REAL*8 Coef(0:1,0:5,0:5),BoundFit(0:1,0:5),pi
real*8 dpi
integer*4 MaxL,MaxM,MaxN
COMMON /EIE_SetW00Coef/Coef,BoundFit,pi,dpi,MaxL,MaxM,MaxN
blat = BoundaryLat00(gmlt)
IF(glat .GT. blat)THEN
Phi=DBLE(gMLT)*dpi/12.D0
colat=90.-glat
bcolat=90.-blat
x=DBLE(colat)*dpi/DBLE(bcolat)
DC=DBLE(Coef(0,0,0))
Z=DC
O=DC
ct=DCOS(x)
dPlm(:,:)=0.D0
CALL DLegendre00(ct,MaxL,MaxM,Plm,dPlm)
!Also find value at outer boundary at angle Pi, or cos(pi)=-1.
CALL DLegendre00(-1.D0,MaxL,MaxM,OPlm,dPlm)
DO l=1,MaxL
Z=Z + Plm(l,0)*DBLE(Coef(0,l,0))
O=O + OPlm(l,0)*DBLE(Coef(0,l,0))
mlimit=MIN(l,MaxM)
DO m=1,mlimit
phim=phi*m
Z=Z + Plm(l,m)*(DBLE(Coef(0,l,m))*DCOS(phim) +
$ DBLE(Coef(1,l,m))*DSIN(phim) )
O=O +OPlm(l,m)*DBLE(Coef(0,l,m))
ENDDO
ENDDO
EpotVal00 = SNGL(Z-O)
ELSE
EpotVal00 = 0.
ENDIF
RETURN
END FUNCTION EpotVal00
************************ Copyright 1996,2001 Dan Weimer/MRC ***********************
************************ Copyright 1996,2001 Dan Weimer/MRC ***********************
*
* Subroutines to calculate the electric potentials from the "Weimer 01" model of
* the polar cap ionospheric electric potentials described in the publication:
* Weimer, D. R., An improved model of ionospheric electric potentials including
* substorm perturbations and application to the Geospace Environment Modeling
* November 24, 1996 event, Journal of Geophysical Research, Vol. 106, p. 407, 2001.
*
* To use, first call procedure SETMODEL01 with the specified input parameters:
* angle: IMF Y-Z clock angle in degrees, 0=northward, 180=southward
* Bt: Magnitude of IMF in Y-Z plane in nT
* Tilt: dipole tilt angle in degrees.
* SWVel: solar wind velocity in km/sec
* SWDen: solar wind density in #/cc
* ALindex: (optional) AL index in nT
*
* The function EPOTVAL01(gLAT,gMLT) can then be used repeatively to get the
* electric potential in kV at the desired location.
* Input coordinates assume use of 'altitude adjusted' corrected geomagnetic
* coordinates for R=1, also refered to as AACGM0.
*
* The function BOUNDARYLAT01(gMLT) can be used to get the latitude of the boundary
* where the potential goes to zero. This boundary is a function of MLT, and
* varies with the SETMODEL01 parameters. The potential is zero everywhere below
* this boundary.
*
* This code is protected by copyright and is distributed
* for research or educational use only.
* Commerical use without written permission from Dan Weimer/MRC is prohibited.
CNCAR Revisions for use at NCAR:
C (1) Change behavior at minimum magnetic latitude. When approaching
C the model equatorial edge (which varies with MLT) the electric
C potential returned used to go to zero discontinuously; although
C intended as a flag, it created artificial gradients in the
C electric field calculation. Now the potential returned is
C constant (that of the minimum latitude) for any latitude at
C or equatorward of the minimum.
C (2) Accomodate running simultaneously 1996 and 2001 versions. To
C avoid name collisions this required: (i) revising names (e.g.,
C adding '01') for differing subprograms, and (ii) relocating
C common routines into another file (weicom.f).
C (3) Pass the coefficients file name and unit number into READCOEF01
C rather than using hard coded values.
C (4) Add wrapper subroutines for non-ANSI trig functions which
C input angles in degrees.
C (5) Add electric field routine (GECMP01) to deterine the electric
C potential gradient.
C (6) Add wrapper routine (WEIEPOT01) for use with AMIE; this is a
C substitute for calling SETMODEL01 and EPOTVAL01.
C (7) Remove blanks in some statements to fit in 72 columns to
C adhere to ANSI Fortran 77.
CNCAR NCAR changes are delimited by "CNCAR"
*
************************ Copyright 1996,2001 Dan Weimer/MRC ***********************
SUBROUTINE DLEGENDRE01(x,lmax,mmax,Plm)
* compute Double Precision Associate Legendre Function P_l^m(x)
* for all l up to lmax and all m up to mmax.
* Returns results in array Plm.
* The recursion formulas keep a count of the exponents of the factor SQRT(1-x^2)
* in both the numerator and denominator, which may cancel each other in the
* final evaluation, particularly with the derivatives. This prevents infinities
* at x=-1 or +1.
* If X is out of range ( abs(x)>1 ) then value is returns as if x=1.
DOUBLE PRECISION x,xx,Plm(0:10,0:10),P(0:10,0:10,0:1),fact,sfact
DOUBLE PRECISION dP(0:10,0:10,0:2),anum,term
DO l=0,lmax
DO m=0,mmax
Plm(l,m)=0.D0
P(l,m,0)=0.D0
P(l,m,1)=0.D0
ENDDO
ENDDO
IF(lmax .LT. 0 .OR. mmax .LT. 0 .OR. mmax .GT. lmax )THEN
Print *,'Bad arguments to DLegendre'
RETURN
ENDIF
* Copy x to xx, and make sure it is in range of -1. to +1.
xx=MIN(x,1.D0)
xx=MAX(xx,-1.D0)
P(0,0,1)=1.D0
IF(lmax.GT.0) P(1,0,1)=xx
IF(lmax.GT.1)THEN
DO L=2,lmax
P(L,0,1)=( (2.D0*L-1)*xx*P(L-1,0,1) - (L-1)*P(L-2,0,1) ) / L
ENDDO
ENDIF
fact=1.D0-xx**2
sfact=DSQRT(fact)
IF(mmax .GT. 0)THEN
DO M=1,mmax
DO L=M,lmax
L2=MAX( L-2 , 0 )
P(L,M,1)= P(L2,M,1) -(2*L-1)*P(L-1,M-1,0)*fact
P(L,M,0)= P(L2,M,0) -(2*L-1)*P(L-1,M-1,1)
ENDDO
ENDDO
ENDIF
DO L=0,lmax
mlimit=MIN(mmax,L)
DO M=0,mlimit
Plm(L,M)=P(L,M,1) + P(L,M,0)*sfact
ENDDO
ENDDO
RETURN
END SUBROUTINE DLEGENDRE01
************************ Copyright 1996,2001 Dan Weimer/MRC ***********************
SUBROUTINE READCOEF01 (udat)
CNCAR Feb 01: Make a subroutine (a.k.a. ReadCoef) from FIRST=TRUE block
C of SETMODEL01 (a.k.a. SetModel) so that one can load the coefficients
C independently of defining geophysical conditions. This mimics the
C 1996 model.
C Sep 01: Change argument list to pass both unit number and file name
C rather than hard coding
CNCAR
INTEGER udat
CHARACTER*30 Copyright
PARAMETER (MJ=3,ML=4,MM=3,MN=2,MO=2)
REAL CS( 0:MJ, 0:1 , 0:MO, 0:1 , 0:ML, 0:MM)
REAL BCS( 0:MJ, 0:1 , 0:MO, 0:1 , 0:MN)
REAL SS( 0:1 , 0:1 , 0:MO, 0:1 , 0:ML, 0:MM)
REAL BSS( 0:1 , 0:1 , 0:MO, 0:1 , 0:MN)
REAL Coef(0:1,0:5,0:5),BoundFit(0:1,0:5),pi
DOUBLE PRECISION dpi
INTEGER*4 maxj,MaxL,MaxM,MaxN,MaxO
COMMON /EIE_AllW01Coefs/MaxJ,MaxO,CS,BCS,SS,BSS
COMMON /EIE_SetW01Coef/MaxL,MaxM,MaxN,Coef,BoundFit,pi,dpi
CNCAR Feb 01: Initialize constants used in GECMP01
C Sep 01: Omit unneeded min lat variables because of switch to
C constant potential at and below min lat (hardcoded
C in EPOTVAL01).
COMMON /EIE_W01CECMP/ ALAMX,STPD,STP2,CSTP,SSTP
C ALAMX = Absolute max latitude (deg) for normal gradient calc.
C STPD = Angular dist (deg) of step @ 300km above earth (r=6371km)
C STP2 = Denominator in gradient calc
PARAMETER ( D2R = 0.0174532925199432957692369076847 ,
+ R2D = 57.2957795130823208767981548147)
STEP = 10.
STPR = STEP/6671.
STPD = STPR*R2D
STP2 = 2.*STEP
CSTP = COS (STPR)
SSTP = SQRT (1. - CSTP*CSTP)
ALAMX = 90. - STPD
CNCAR
CNCAR Sep 01: udat is now an argument
C Assume file has been opened at unit elsewhere
CNCAR
c OPEN (UNIT=udat,FILE=cfile,STATUS='OLD',form='UNFORMATTED')
READ (udat) Copyright
PRINT *,Copyright
READ (udat) Maxj,MaxL,MaxM,MaxN,MaxO
If (maxj.NE.MJ .OR. MaxL.NE.ML .OR. MaxM.NE.MM .OR.
$ MaxN.NE.MN .OR. MaxO.NE.MO) Then
PRINT *,'Data File Error'
STOP !Data file did not match size expected for arrays
Endif
READ (udat) CS
READ (udat) BCS
READ (udat) SS
READ (udat) BSS
CLOSE (udat)
pi=2.*ASIN(1.)
dpi=2.D0*DASIN(1.D0)
RETURN
END SUBROUTINE READCOEF01
************************ Copyright 1996,2001 Dan Weimer/MRC ***********************
CNCAR Sep 01: Change name from SetModel to be distinct
SUBROUTINE SetModel01 (angle,Bt,Tilt,SWVel,SWDen,ALindex,UseAL)
C SUBROUTINE SetModel (angle,Bt,Tilt,SWVel,SWDen,ALindex,UseAL)
CNCAR
*
* Calculate the complete set of spherical harmonic coeficients,
* given an aribitrary IMF angle (degrees from northward toward +Y),
* magnitude Bt (nT), dipole tilt angle (degrees),
* solar wind velocity (km/sec), SWDen (#/cc),
* ALindex (nT), and Logical flag to use optional AL index.
*
* Sets the value of Coef and Boundfit in the common block SetW01Coef.
*
REAL angle,Bt,Tilt,SWVel,SWDen,ALindex
C LOGICAL First,UseAL
LOGICAL UseAL
CNCAR Feb 01: Move logic block to subroutine RdCoef01
C DATA First/.TRUE./
C SAVE First
C INTEGER unit
C CHARACTER*15 cfile
C CHARACTER*30 Copyright
PARAMETER (MJ=3,ML=4,MM=3,MN=2,MO=2)
REAL CS( 0:MJ, 0:1 , 0:MO, 0:1 , 0:ML, 0:MM)
REAL BCS( 0:MJ, 0:1 , 0:MO, 0:1 , 0:MN)
REAL SS( 0:1 , 0:1 , 0:MO, 0:1 , 0:ML, 0:MM)
REAL BSS( 0:1 , 0:1 , 0:MO, 0:1 , 0:MN)
REAL XA(0:MJ),XB(0:MJ),FSC(0:1,0:4),PSS(0:1)
REAL Coef(0:1,0:5,0:5),BoundFit(0:1,0:5),pi
DOUBLE PRECISION dpi
INTEGER*4 i,j,k,l,m,n,o
INTEGER*4 maxj,MaxL,MaxM,MaxN,MaxO
COMMON /EIE_AllW01Coefs/MaxJ,MaxO,CS,BCS,SS,BSS
COMMON /EIE_SetW01Coef/MaxL,MaxM,MaxN,Coef,BoundFit,pi,dpi
CNCAR Feb 01: Move logic block to subroutine RdCoef01
C All First=TRUE in new subroutine ReadCoef
C If(First)Then
C cfile='w01.dat' !make sure correct ENDIAN type file is used.
C unit=99
C OPEN(UNIT=unit,FILE=cfile,STATUS='OLD',form='UNFORMATTED')
C READ(unit) Copyright
C PRINT *,Copyright
C READ(unit) Maxj,MaxL,MaxM,MaxN,MaxO
C If(maxj.NE.MJ .OR. MaxL.NE.ML .OR. MaxM.NE.MM .OR.
C $ MaxN.NE.MN .OR. MaxO.NE.MO)Then
C PRINT *,'Data File Error'
C STOP !Data file did not match sixe expected for arrays