European Space Agency

Royal Belgian Institute for Aeronomy

uc190 - control parameters, set 1

subroutine  uc190()

Synopsis

INCLUDE 'unilib.h'

COMMON /UC190/ prop, stepx, stpmin, umsq, upsq, uk2, uk3,
               epskm, epsrel, stplst, xclat, kmflg, kum533

REAL*8         prop, stepx, stpmin
REAL*8         umsq, upsq, uk2, uk3
REAL*8         epskm, epsrel, stplst, xclat
INTEGER*4      kmflg, kum533

Arguments

prop

Proportionality factor between the radius of curvature and the step size

stepx

Maximum step size

stpmin

Minimum step size

umsq, upsq, uk2, uk3

Constants used in Runge-Kutta calculation

epskm

Altitude precision

epsrel

Relative magnetic field precision

stplst

Step size near a point of interest

xclat

Not used

kmflg

Flag for ul240()

kum533

Flag for um533()

Description

The common blocks uc190 and uc192 are used to specify parameters which control the execution of the UNILIB library. The arguments of common block uc190 are more specific to the tracing of magnetic field line segment by the Runge-Kutta algorithm. The arguments of both common blocks are initialized by the subroutine ut990().

KMFLAG Values

kmflg	description
0,10	The magnetic dipole moment defined by McIlwain is used, e.g. to compute Hilton’s function.
1,11	The magnetic dipole moment of the current magnetic field model is used, e.g. to compute Hilton’s function.
0,1	The equatorial pitch angle is evaluated using \(B_0 = M/L^3\) for the lowest magnetic field intensity on a field line segment, where M is the magnetic dipole moment.
10,11	The equatorial pitch angle is evaluated using the lowest magnetic field intensity encountered along the current field line segment.

History

• In version 1.10 and earlier, the argument nxstp was defined in the common block uc190 instead of the argument kum533. The argument nxstp was used to control the maximum number of steps allowed during the tracing of a field line segment. The value of the maximum step number is now only fixed by the value of parameter nx170.

Dependencies

Used by

• ul225 - evaluate invariant radius and latitude

  kmflg

• ul220 - get information on a magnetic field line segment

  epsrel

• ul230 - evaluate the integral invariant coordinate I

  umsq, upsq and epsrel

• ul240 - evaluate the Hilton’s function

  kmflg

• ul242 - inverse the Hilton function

  kmflg

• ul245 - equatorial pitch angle

  kmflg

• ud319 - transfer a field line segment from common block uc170 to uc130

  epsrel

• ud330 - evaluate the third invariant

  kmflg

• ud332 - evaluate the magnetic flux through a spherical pie

  epskm

• uf410 - search the geographic position of a magnetic field line

  epskm

• uf411 - search a local magnetic equator

  epskm

• uf415 - rebuild the labels of the field line

  epsrel

• uf420 - trace a magnetic field line segment passing through a given position

  epskm and epsrel

• uf422 - follow a field line until a boundary condition is reached

  prop, stepx, stpmin, epskm, epsrel and stplst

• uf423 - Runge Kutta step

  prop, stepx, stpmin, umsq and upsq

• uf426 - interpolating an extremum of B

  prop, stepx, stpmin, epskm and stplst

• uf427 - interpolating a value of B

  prop, stepx, stpmin, epsrel and stplst

• uf428 - interpolating an altitude

  prop, stepx, stpmin, epskm and stplst

• uf429 - transpose a field line segment

  uk2 and uk3

• um533 - evaluate distance to the magnetopause

  kum533

• ut986 - pass general variables to IDL

  kmflg

Modified by

• ut990 - initialize the UNILIB library

  prop, stepx, stpmin, umsq, upsq, uk2, uk3, epskm, epsrel, stplst, kmflg and kum533.

See also

• uc192 - control parameters, set 2

Examples

None

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UNILIB/tags/v3.02