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NAME:
GAL_CNTR
PURPOSE:
Flag data points close to the galactic center
CATEGORY:
Data processing
CALLING SEQUENCE:
subroutine GAL_CNTR(iSc,iCnt,NST,NS,LL,PP,ZZ)
INPUTS:
iSc integer 1=Helios A, 2=Helios B
iCnt integer # observations
NST,NS integer range of sectors (modified sectors #)
LL(iCnt) real ecliptic longitude of Sun
PP(iCnt) integer =1,2; photometer ID
ZZ(NST:NS,iCnt) real intensities
OUTPUTS:
ZZ(NST:NS,iCnt) real intensities
CALLS: ***
BadR4
CALLED BY:
READ_HOS
SIDE EFFECTS:
No corrections are made for Helios B (iSc=2)
PROCEDURE:
When the ecliptic longitude of a sector falls inside the range
specified in arrays GALMIN,GALMAX (indicating the range of ecliptic
longitude where the galactic center contributes significantly to the
signal) the intensity is flagged (set to BadR4())
MODIFICATION HISTORY:
???-????, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
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NAME:
GAMMALN
PURPOSE:
Calculate natural logarithm of gamma function for X>1
CATEGORY:
Math: special functions
CALLING SEQUENCE:
function GAMMALN(XX)
INPUTS:
XX real*4 (read-only) x-value where gamma fnc is evaluated
OUTPUTS:
GAMMALN real*4 logarithm of gamma function in X
SIDE EFFECTS:
RESTRICTIONS:
PROCEDURE:
Lanczos formulae. Calculations are performed in double precision.
MODIFICATION HISTORY:
Numerical Recipes, p. 157.
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NAME:
GaussLookup
PURPOSE:
Calculates exp(-x*x-y*y) using lookup table
CATEGORY:
Math
CALLING SEQUENCE:
function GaussLookup(X,Y)
INPUTS:
X real X-coordinate
Y real Y-coordinate
OUTPUTS:
F real fnc value
CALLS: ***
FLINT
CALLED BY:
GridSphere3D, GridSphereRange, GridSphereWeight, RebinSphere
SEE ALSO:
CosLookup, SinLookup
MODIFICATION HISTORY:
SEP-2003, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
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NAME:
Get2Dval
PURPOSE:
2D linear interpolationInterpolates values from positions
specified as XC,XL (modified Carrington variable, latitude (deg)
CATEGORY:
Data processing
CALLING SEQUENCE:
subroutine Get2Dval(XCbeg,XCend,nLng,nLat,F2D,N,XC,XL,FF)
INPUTS:
(all input is read-only)
nLng integer # longitudes
nLat integer # latitudes
F2D(nLng,nLat) real 2D array (longitude, latitude)
N integer # points
XC(N) real Modified Carrington variable
XL(N) real Heliographic latitude (deg)
OUTPUTS:
FF(N) real Interpolated function values
CALLS: ***
FLINT
CALLED BY:
MkGModel, MkVModel, MkVObsn360
INCLUDE:
include 'mapangles.h'
PROCEDURE:
> The modified Carrington variable is mapped to the range [1,nLng]
The latitude is mapped to the range [1,nLat]
The distance is mapped to the range [1,nRad]
> For each point, if any of the neighbours contains a bad value, or if any of the
coordinates is more than one bin width outside the index ranges, then the value
BadR4() is returned (see FLINT).
MODIFICATION HISTORY:
MAY-1997, Paul Hick (UCSD; pphick@ucsd.edu)
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NAME:
Get3DTval
PURPOSE:
3D linear interpolationInterpolates values from positions
specified as XC,XL,RP (modified Carrington variable, latitude (deg) and
time (in XC)
CATEGORY:
Data processing
CALLING SEQUENCE:
call Get3TDval(XCbe,XCtbeg,XCtend,nLng,nLat,nT,F3D,N,XC,XL,TI,FF)
INPUTS: (all input is read-only)
XCbe(2,nT) real Beginning and ending Carrington variables
XCtbeg double precision Beginning of time intervals
Xctend double precision Ending of time intervals
nLng integer # longitudes
nLat integer # latitudes
nT integer # time points
F3D(nLng,nLat,nT) real 3D array (longitude, latitude, time)
N integer # points
XC(N) real Modified Carrington variable
XL(N) real Heliographic latitude (deg)
TI(N) double precision Carrington variable value from first time
OUTPUTS:
FF(N) real Interpolated function values
CALLS: ***
FLINT
CALLED BY:
Extractd, MkGModeltdn, MkVModeltd, shift_MOD [1], shift_MOD [2], write3D_infotd3D
INCLUDE:
include 'mapcoordinates.h'
PROCEDURE:
> The modified Carrington variable is mapped to the range [1,nLng]
The latitude is mapped to the range [1,nLat]
The time is mapped to the range [1,nT]
> For each point, if any of the neighbours contains a bad value, or if any of the
coordinates is more than one bin width outside the index ranges, then the value
BadR4() is returned (see FLINT).
MODIFICATION HISTORY:
MAY-1997, Paul Hick (UCSD; pphick@ucsd.edu)
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NAME:
Get3Dval
PURPOSE:
3D linear interpolationInterpolates values from positions specified as
XC,XL,RP (modified Carrington variable, latitude (deg) and distance (AU)
CATEGORY:
Data processing
CALLING SEQUENCE:
subroutine Get3Dval(XCbeg,Xcend,RR,dRR,nLng,nLat,nRad,F3D,N,XC,XL,RP,FF)
INPUTS: (all input is read-only)
RR real
dRR real Distance between individual maps (in AU)
nLng integer # longitudes
nLat integer # latitudes
nRad integer # DF maps formed (height begins ~0 AU)
F3D(nLng,nLat,nRad) real 3D array (longitude, latitude, radial distance)
N integer # points
XC(N) real Modified Carrington variable
XL(N) real Heliographic latitude (deg)
RP(N) real Heliocentric distance (AU)
OUTPUTS:
FF(N) real Interpolated function values
CALLS: ***
FLINT
CALLED BY:
ExtractInsitu, MkPos, ipsd
INCLUDE:
include 'mapcoordinates.h'
PROCEDURE:
> The modified Carrington variable is mapped to the range [1,nLng]
The latitude is mapped to the range [1,nLat]
The distance is mapped to the range [1,nRad]
> For each point, if any of the neighbours contains a bad value, or if any of the
coordinates is more than one bin width outside the index ranges, then the value
BadR4() is returned (see FLINT).
MODIFICATION HISTORY:
MAY-1997, Paul Hick (UCSD; pphick@ucsd.edu)
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NAME:
Get4Dval
PURPOSE:
4D linear interpolationInterpolates values from positions
specified as XC,XL,RP (modified Carrington variable, latitude (deg) and
distance (AU)
CATEGORY:
Data processing
CALLING SEQUENCE:
call Get4Dval(NN,XCbe,XCtbeg,XCtend,RR,dRR,nLng,nLat,nMap,nT,
F4D,N,TI,XC,XL,RP,FF)
INPUTS: (all input is read-only)
NN integer # of F4D parameters
XCbe(2,nT) real Beginning and ending Carrington variables
XCtbeg double precision Beginning of time intervals
Xctend double precision Ending of time intervals
RR real Beginning map distance
dRR real Distance between individual maps (in AU)
nLng integer # longitudes
nLat integer # latitudes
nMap integer # DF maps formed (height begins ~0 AU)
nT integer # time points
F4D(nLng,nLat,nMap,nT) real 4D array (longitude, latitude, radial distance, time)
N integer # points
TI(N) real Carrington variable value from first time
XC(N) real Modified Carrington variable
XL(N) real Heliographic latitude (deg)
RP(N) real Heliocentric distance (AU)
OUTPUTS:
FF(NN,N) real Interpolated function values
CALLS: ***
FLINT
CALLED BY:
Extractd, Extractd3d, MkPostd, ipsdt, write3D_infotd3D
INCLUDE:
include 'mapcoordinates.h'
PROCEDURE:
> The modified Carrington variable is mapped to the range [1,nLng]
The latitude is mapped to the range [1,nLat]
The distance is mapped to the range [1,nMap]
> For each point, if any of the neighbours contains a bad value, or if any of the
coordinates is more than one bin width outside the index ranges, then the value
BadR4() is returned (see FLINT).
MODIFICATION HISTORY:
MAY-1997, Paul Hick (UCSD; pphick@ucsd.edu)
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NAME:
get_compiler
CALLING SEQUENCE:
subroutine get_compiler(f77id)
CALLED BY:
Time2System
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NAME:
get_compiler
CALLING SEQUENCE:
subroutine get_compiler(f77id)
CALLED BY:
Time2System
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NAME:
GetLOSValue
PURPOSE:
4D linear interpolation. Interpolates values from positions
specified as modified Carrington variable (XC), latitude (XL), heliocentric
distance (RP) and time (XT).
CATEGORY:
Data processing
CALLING SEQUENCE:
subroutine GetLOSValue(iRow,nRow,XCbegMAT,XCendMAT,F3D,N,PPlos,FFlos)
INPUTS:
iRow integer coordinate to interpolate on (1..nRow)
nRow integer # coordinates
XCbegMAT(nTim) real Start Carrington variable
XCendMAT(nTim) real End Carrington variable
F3D(nRow,nLng,nLat,nRad,nTim)real 5D array (coordinate, longitude, latitude,
radial distance, time)
N integer # points
PPlos(4,N) real Lng/lat/rad/time of points on los
OUTPUTS:
FFlos(nRow,N) real Interpolated function values
(Only FFlos(iRow,*) is modified)
CALLS: ***
FLINT, T3D_get_grid, T3D_iget
CALLED BY:
LOSIntegralG, LOSIntegralV, LOSProjection
INCLUDE:
include 't3d_param.h'
include 't3d_array.h'
include 't3d_index.h'
include 't3d_grid_fnc.h'
include 't3d_loc_fnc.h'
PROCEDURE:
> The modified Carrington variable is mapped to the range [1,nLng]
The latitude is mapped to the range [1,nLat]
The distance is mapped to the range [1,nRad]
> For each point, if any of the neighbours contains a bad value, or if any of the
coordinates is more than one bin width outside the index ranges, then the value
BadR4() is returned (see FLINT).
MODIFICATION HISTORY:
MAY-1997, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
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NAME:
GinBar
PURPOSE:
Duummy routine for Windows and Linux
for functions containing calls to GRPACK functions
CALLED BY:
HOSPlot, HOSPlot_EditPoints, HOSPlot_bCommand, TheFit
PROCEDURE:
Needed by: MapReadSrf
MODIFICATION HISTORY:
JAN-2001, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
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NAME:
GIPSCAST
PURPOSE:
Calculates aftcast and forecast G values at two day intervals.
CATEGORY:
Linear interpolation
CALLING SEQUENCE:
subroutine GIPSCAST(MJDEarth,nX,Gval,NS)
INPUTS:
MJDEarth real*8 modified Julian day at the
position of the Earth
nX integer # latititudes
Gval(-nX/2:nX/2) real G values at latitude of Earth
NS integer # fore- and aftcast steps (2 day
steps)
OUTPUTS: (to file)
DOYG(2,-NS:NS) real array with current,preceding,
and subsequent days of the year (at two day intervals) and the
corresponding G values for those days
DEL_G(-NS:NS) real differences between
interpolated G values and the G value presently at Earth
CALLS: ***
Julian, Say, bOpenFile, iFilePath, iFreeLun
INCLUDE:
include 'dirspec.h'
include 'openfile.h'
include 'sun.h'
MODIFICATION HISTORY:
JUL-1992, Kari Winfield (UCSD)
AUG-1992, Susan Rappoport (UCSD)
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NAME:
GIPSIMP
PURPOSE:
Calculates aftcast and forecast G values at two day intervals.
CATEGORY:
Linear interpolation
CALLING SEQUENCE:
subroutine GIPSIMP(cVFile,MJDEarth,nX,Gval,NS)
INPUTS:
cVFile character*(*) name of IMP data file
MJDEarth real*8 modified julian day at the
position of the Earth
nX integer # latititudes
Gval(-nX/2:nX/2)real G values at latitude of Earth
0 = no G-value is available
NS integer # fore- and aftcast steps (2 day steps)
OUTPUTS: (to file)
DOYG(2,-NS:NS) real array with current, preceding, and
subsequent days of the year (at two day intervals) and the
corresponding G values for those days
DEL_G(-NS:NS) real differences between interpolated G values
and the G value presently at Earth
CALLS: ***
Julian, Say, bOpenFile, iFreeLun
INCLUDE:
include 'openfile.h'
include 'sun.h'
MODIFICATION HISTORY:
July 1992, Kari Winfield (UCSD)
August 1992, Susan Rappoport (UCSD)
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NAME:
grdisp
PURPOSE:
Defines parameters needed by GRPACK plotting package.
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NAME:
GridFill
PURPOSE:
Removes empty bins. An empty bin is given the average over all
neighbours with valid function values.
CATEGORY:
Plotting: contours
CALLING SEQUENCE:
subroutine GridFill(nFillIn,nX,nY,Z,NSIDE,Zmin,Zmax)
INPUTS:
nFill integer The three least-significant digits of nFill are used:
mod(nFill,1000) >= 100: messages to screen are suppressed
mod(nFill, 100) >= 10: Z(.,.,2) is used as output array
(otherwise Z(*,*,2) is never accessed)
mod(nFill, 10) >= 0: threshold on # valid neighbours
If zero then all empty bins with extrapolated values
are filled in. If larger than zero (and at most 8)
only empty bins with valid neighbours equal or larger
than the specified threshold are filled in.
nX,nY integer dimensions of input grid
Z(nX,nY) or Z(nX,nY,2) !!! Z(nX,nY) can be used only if nFill < 10 !!!
real
Z(.,.,1) array of function values (BadR4() indicates bad value)
Z(.,.,2) used as scratch space; content does not matter
NSIDE(nX,nY,-1:1,-1:1)
integer*1 scratch array
OUTPUTS:
Z(nX,nY,2) real
Z(.,.,1) array of function values with empty bins removed
or (only nFill>0)
Z(.,.,2) array identifying the extrapolated values:
= -1 contents of bin is same as valid input value
= 1 contents of bin is extrapolated value
nFill>0 only:
= 0 empty bin with less than nFill neighbours
Z(.,.,1) = BadR4() (same as input).
Zmin real minimum function value (incl interpolated fncv)
Zmax real maximum function value (incl interpolated fncv)
CALLS: ***
ArrR4GetMinMax, ArrR4Mask, BadR4, GridFillWeight, Int2Str, Say, Str2Str
iArrR4ValuePresent, iGridScan
CALLED BY:
GridSphere3D, GridSphereRange, GridSphereWeight, MKVTRACE, RebinSphere, ipsd, ipsdt
ipsg2, ipsg2s, ipsg2t, smei_get_lsff
RESTRICTIONS:
If the input array Z is declared in the calling program as Z(nX,nY)
then nFill MUST be less than 10 to avoid accessing Z(*,*,2)
PROCEDURE:
> If nFill = 0 then:
Step 1: for each empty bin, count the number of non-empty neighbours
Step 2: find the subset of empty bins with the maximum number of
non-empty neighbours
Step 3: for the subset of step 2, calculate the average over the non-
empty neighbours and assign this average to the empty bin
Step 4: Go to step 1
Repeat until there are no empty bins left.
> nFill > 0:
Step 1: for each empty bin, count the number of non-empty neighbours
Step 2: find the subset of empty bins with nFill or more non-empty
neighbours
Step 3: for the subset of step 2, calculate the average over the non-
empty neighbours and assign this average to the empty bin
Step 4: Return.
> Neighbouring function values are averaged using the function
GridFillWeight to get weighting factors. The default function
returns GridFillWeight = 1 (see end of this file).
Override the default function with a different version by
making sure it precedes this file in the compilatation.
The function has the form
function GridFillWeight(I,J,INX,JNY,ZN)
I,J and INX,JNY are the indices of empty bin and neighbour bin.
ZN the function value in the neighbour bin.
> 'Bad' bins are usually identified by testing for BadR4().
This can be modified using GridFillBad:
rbad = BadR4Set(0.0)
call GridFill(nFillIn,nX,nY,Z,NSIDE,Zmin,Zmax)
rbad = BadR4Set(rbad)
The second BadR4Set call restores the original BadR4 value
MODIFICATION HISTORY:
1990, Paul Hick (UCSD/CASS)
APR-1999, Paul Hick (UCSD/CASS)
simplified code by introducing iGridScan function
MAY-2002, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
added option to suppress output messages
NOV-2004, Paul Hick (UCSD/CASS)
Added entry point GridFillBad to modify the actual
value used to indicate 'bad'.
FEB-2005, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
Removed GridFillBad again. The BadR4 value can
now be set by BadR4Set.
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NAME:
GridFillWeight
PURPOSE:
Sample for use in GridFill
CALLING SEQUENCE:
function GridFillWeight(I,J,INX,JNY,ZN)
CALLED BY:
GridFill
MODIFICATION HISTORY:
SEP-2007, Paul Hick (UCSD/CASS)
Extracted from gridfill.f
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NAME:
GridRan2Reg
PURPOSE:
Generate function values in a regular grid of NX by NY points.
The input function values are specified on a set of NPTS random
points XP,YP
CATEGORY:
Plotting: contours
CALLING SEQUENCE:
subroutine GridRan2Reg(DistIn,NPTS,XP,YP,ZP,XB,YB,XE,YE,NX,NY,Z)
INPUTS:
DistIn real data points closer than abs(Dist) grid
spacings from a grid point are included
in the averaging
If Dist < 0 then input fnc-values in arrays Z and ZP of
BadR4() values are disregarded in the averaging
NPTS integer number of points in the random set
If NPTS < 0 then Z returns standard deviations
XP(NPTS) real X/Y-coordinates of points in the
YP(NPTS) random set in user-specified units
ZP(NPTS) real function values in the random set
XB,YB real X/Y-coordinate of grid point (1,1)
in user units
XE,YE real X/Y-coordinate of grid point (NX,NY)
in user units
NX,NY integer dimensions of regular output grid
OUTPUTS:
Z(NX,NY) real grid function values.
If no function value was calculated for
a particular grid point the value
BadR4() is returned
CALLS: ***
ArrI4Zero, ArrR4DivideByArrI4, ArrR4Zero, BadR4, Say
SEE ALSO:
GridReg2Reg
RESTRICTIONS:
> The user units for XB,XE,YB,YE should be the same as for XP and YP
> The # elements in the output grid are limited to the
value set for parameter NMAX. Currently NMAX=10000.
PROCEDURE:
> BadR4() is used to identify invalid fnc-values in in- and output Z
> The output grid defines a regular grid of NYxNX squares.
The function values Z are calculated by averaging over points ZP
inside a grid square.
MODIFICATION HISTORY:
1989-1990, Paul Hick (SRON,MPAE,UCSD/CASS)
1993, Paul Hick (UCSD/CASS; pphick@ucsd.edu); complete revision
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NAME:
GridReg2Reg
PURPOSE:
Generate function values in a regular grid of NX by NY points. The
input function values are specified on a regular grid of MX by MY points
CATEGORY:
Plotting: contours
CALLING SEQUENCE:
subroutine GridReg2Reg(Dist,MX,MY,ZP,NX,NY,Z)
INPUTS:
Dist real data points closer than abs(Dist) grid
spacings from a grid point are included
in the averaging
If Dist < 0 then input fnc-values in arrays Z and ZP of
BadR4() values are disregarded in the averaging
MX,MY integer dimensions of regular input grid
ZP(MX,MY) real function values in input grid
NX,NY integer dimensions of regular output grid
OUTPUTS:
Z(NX,NY) real grid function values.
If no function value was calculated for
a particular grid point the value
BadR4() is returned
CALLS: ***
BadR4
SEE ALSO:
GridRan2Reg
RESTRICTIONS:
The user units for XB,XE,YB,YE should be the same as for XP and YP
PROCEDURE:
> BadR4() is used to identify invalid fnc-values in in- and output Z
> The output grid defines a regular grid of NYxNX squares.
The function values Z are calculated by averaging over points ZP
inside a grid square.
MODIFICATION HISTORY:
1989-1990, Paul Hick (SRON,MPAE,UCSD/CASS)
1993, Paul Hick (UCSD/CASS; pphick@ucsd.edu); complete revision
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NAME:
GridSphere2D
PURPOSE:
Fills 'holes' and/or smooths a 2D array using a Gaussian weighting function.
The array dimensions represent a regular grid in spherical coordinates
(longitude and latitude). The third is the grid in radial distance.
CALLING SEQUENCE:
subroutine GridSphere2D(dXC,nLng,nLat,nR,Z,WidDeg,iBadZ,WThreshold,ClipLng)
INPUTS:
real dXC ! range of Carrington variable covered by nLng
! i.e. number of 360 deg rotations.
integer nLng ! # longitudes
integer nLat ! # latitudes
integer nR ! # radial distances
real Z(nLng,nLat,nR) ! 3D array of function values
real WidDeg ! Width of Gaussian used for angular
! smoothing (in degrees) (WidDeg<0 has
! special meaning; see PROCEDURE)
integer iBadZ ! 0: Invalid elements remain invalid;
! valid elements are replaced by a
! smoothed value
! 1: All elements (valid and invalid) are
! replaced by smoothed values.
! 2: Invalid elements are replaced by
! smoothed values; valid elements remain
! untouched.
!
! The following two options are useful if all
! bad bins have to be filled in with something.
! Use them at your own risk (see PROCEDURE).
!
! 3: Same as iBadZ=1, but if any invalid
! elements remain at the end, these are
! all filled in by a call to GridFill
! 4: Same as iBadZ=2, but if any invalid
! elements remain at the end, these are
! all filled in by a call to GridFill
!
! >=10: use open grid for longitude and latitude
real WThreshold ! The replacement by a smoothed value is
! made only if total weight is
! larger than/equal to the threshold value.
! (see PROCEDURE).
real ClipLng ! Longitude difference (see PROCEDURE)
! (usually set to zero).
OUTPUTS:
real Z(nLng,nLat,nR) smoothed array of function values
CALLS: ***
GridSphere3D
CALLED BY:
MkDMap, MkDMaptdn, MkShift, MkShiftdn, MkVMap, MkVMaptdN, SW_Model_Kinematic, ipsd
ipsdt, ipsg2, ipsg2s, ipsg2t, shift_MOD [1], shift_MOD [2], sim_MOD, smei_skyd_fts
smei_skyd_init, smei_skyd_make, smei_skyd_sky
PROCEDURE:
GridSphere2D is a one-line wrapper around GridSphere3D
MODIFICATION HISTORY:
FEB-1997, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
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NAME:
GridSphere3D
PURPOSE:
Fills 'holes' and/or smooths a 3D array using a Gaussian weighting function.
Two of the array dimensions represent a regular grid in spherical
coordinates (longitude and latitude). The third represents a regular
grid in radial distance.
CALLING SEQUENCE:
subroutine GridSphere3D(dXC,nLng,nLat,nR,Z,WidDeg,R1,iBadZ,WThreshold,ClipLng)
INPUTS:
dXC real range of Carrington variable covered by nLng
i.e. number of 360 deg rotations.
nLng integer # longitudes
nLat integer # latitudes
nR integer # radial distances
Z(nLng,nLat,nR) real 3D array of function values
WidDeg real Width of Gaussian used for angular
smoothing (in degrees) (WidDeg<0 has
special meaning; see PROCEDURE)
R1 real (3D version only)
R1 > 0:Radial distance for inner boundary (in
grid spacings), i.e. location of Z(*,*,1)
R1=0 IS INVALID; MUST BE R1>0
R1 < 0:(value does not matter)
suppresses the radial smoothing, i.e.
each subarray Z(*,*,i),i=1,nR is
2D smoothed over longitude and latitude only.
iBadZ integer 0: Invalid elements remain invalid;
valid elements are replaced by a
smoothed value
1: All elements (valid and invalid) are
replaced by smoothed values.
2: Invalid elements are replaced by
smoothed values; valid elements remain
untouched.
The following two options are useful if all
bad bins have to be filled in with something.
Use them at your own risk (see PROCEDURE).
3: Same as iBadZ=1, but if any invalid
elements remain at the end, these are
all filled in by a call to GridFill
4: Same as iBadZ=2, but if any invalid
elements remain at the end, these are
all filled in by a call to GridFill
>=10: Use open grid for longitude and latitude (?)
>=100: Use lookup table for Gaussian
WThreshold real The replacement by a smoothed value is
made only if total weight is
larger than/equal to the threshold value.
(see PROCEDURE).
ClipLng real Longitude difference (see PROCEDURE)
(usually set to zero).
OUTPUTS:
Z(nLng,nLat,nR) real smoothed array of function values
CALLED BY:
GridSphere2D
INCLUDE:
include 'math.h'
CALLS: ***
ArrR4Copy, BadR4, GaussLookup, GridFill, Say, iArrR4ValuePresent
RESTRICTIONS:
> GridSphere3D uses internal scratch arrays, which are
dimensioned using 3 parameters, LNG,LAT and LNR. If the scratch
arrays are too small, program execution stops.
> iBadZ=3 and iBadZ=4:
GridFill uses a 2D algorithm to fill in holes. If nR>1 then GridFill
is applied to each level k=1,nR separately.
PROCEDURE:
> Invalid or 'Bad' array elements are indicated by the value BadR4()
> The 1st dimension represents a regular grid in longitude covering
[0,360] degrees, i.e. Lng(i) = 360*(i-1)/(nLng-1), i=1,nLng.
The 2nd dimension represents a regular grid in latitude covering
[-90,+90] degrees, i.e. Lat(j) = -90*[-1+2*(j-1)/(nLat-1)], j=1,nLat.
The 3rd dimension represents a regular grid in radial distance,
i.e. R(k) = R1+k-1
> Obviously, 2D arrays can be smoothed by setting nR=1.
> GridSphere2D is just a special call to GridSphere3D with R1=-1 (the
value does not matter as long as it's negative).
> The weighting is Gaussian with weight=1 at the origin. To avoid loosing
valid elements for iBadZ=0 or 1, set the threshold weight to a
value less than 1.
> The angular weighting factor involves the angular distance between
two locations on a sphere. The points are connected by two arcs,
one is the minimum angular distance A (0<A<180), the other is the
complementary angle AC=360-A (180<AC<360).
If ClipLng=0 the angle A is always used. As a result, the smoothed
function value for small/large longitudes will depend on the input
function values at large/small longitudes with fairly large weighting
factors (since the angular distance is small).
This effect can be suppressed by setting ClipLng to a non-zero value.
If the longitude difference abs(Lng(i1)-Lng(i2)) is larger than
ClipLng, then the corresponding element is excluded.
BE CAREFUL WHEN USING THIS OPTION. In particular, setting
ClipLng to values around 180 degrees affects the smoothing for
points near the poles (where points with a wide range of longitude
differences are close together). As a guideline
ClipLng > 180+3*WidDeg is probably not a bad place to start.
> If WidDeg > 0, the smoothing procedure is speeded up by looping
over only part of the array when calculating the smoothed function
value. Excluded are all elements which are more than 3 times the
Gaussian width away from the element for which the smoothed value is
calculated (the weight would be less than exp(-9)). The exclusion
is based on an approximate calculation of the distance between points.
Near the poles there may be a problem (see the explanation in the code),
but I think it's under control now.
In case you don't trust the result set WidDeg to a negative value.
If WidDeg <0, then the absolute value is used as Gaussian width, and
the whole array is used in the calculation of the smoothed average.
The procedure will be a LOT slower though.
> If ClipLng=0 then the averaging algorithm is mod(XCend-XCbeg), i.e. if
in the input array column 1 (XC = XCend) and column nLng (XC = XCbeg)
are the same this is also true for the output array.
HOWEVER this symmetry is broken if iBadZ=3 or 4 because of the extra
call to GridFill.
MODIFICATION HISTORY:
FEB-1997, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
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NAME:
GridSphereRange
PURPOSE:
CALLING SEQUENCE:
entry GridSphereRange(range_lo_,range_hi_)
CALLS: ***
ArrR4Copy, BadR4, GaussLookup, GridFill, Say, iArrR4ValuePresent
CALLED BY:
smei_skyd_fts, smei_skyd_init, smei_skyd_make, smei_skyd_sky
MODIFICATION HISTORY:
MAY-2007, Paul Hick (pphick@ucsd.edu)
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NAME:
GridSphereWeight
PURPOSE:
CALLING SEQUENCE:
entry GridSphereWeight(nLng,nLat,nR,Z,ZThreshold_)
CALLS: ***
ArrR4Copy, BadR4, GaussLookup, GridFill, Say, iArrR4ValuePresent
CALLED BY:
smei_skyd_fts, smei_skyd_init, smei_skyd_make, smei_skyd_sky
MODIFICATION HISTORY:
MAY-2007, Paul Hick (pphick@ucsd.edu)
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NAME:
grpack
PURPOSE:
Parameter definitions needed by GRPACK plot package
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NAME:
GTODEN
PURPOSE:
Used by EGIPSY to create density maps
CALLING SEQUENCE:
function GTODEN(IDFNC,G)
INPUTS:
IDFNC integer ID for indentifying conversion formulae
if < 0 in GTODEN the inverse is applied
G real G-value to be converted
OUTPUTS:
GTODEN real Calculated density
CALLS: ***
BadR4
CALLED BY:
ConvertG2D
SEE ALSO:
NRGTODEN, STRGTODEN
PROCEDURE:
To add additional conversions from G value to density, do the following
(the places where these changes should be made is indicated in the code)
> 1. Add code for the conversion. This would look like:
else if (IDFNC .eq. ?) then
<more code>
GTODEN = <return value for density>
else if (IDFNC .eq. -?) then
<more code>
GTODEN = <return value for G-value from inverse function>
? stands for the next higher IDFNC value not yet in use
> 2. Add a string descriptor for the function. This would look like:
else if (IDFNC .eq. ?) then
cStr = '<string desciptor>'
? is the same value as the one in the previous step
> 3. Increase NRGTODEN. The line defining the new NRGTODEN will usually be:
NRGTODEN = ?
where ? again is the same value as in the previous steps
MODIFICATION HISTORY:
MAY-1994, Paul Hick (UCSD)
