European Space Agency

Royal Belgian Institute for Aeronomy

ul230 - evaluate the integral invariant coordinate I

subroutine  ul230(finv, ifail)

Parameters:

• finv [real8,out] :: Integral invariant coordinate

• ifail [integer4,out] :: error flag (see Diagnostics)

Description

The subroutine ul230() evaluates the integral invariant coordinate I for the current magnetic field line segment stored in the common block uc170. The integration algorithm takes advantage from the fact that the magnetic field line segment has been traced by the fourth-order Runge-Kutta method. The integral invariant coordinate I is mainly used to determine McIlwain’s shell parameter L.

References

• Heynderickx, D., and Lemaire, J., Improvements to trapped radiation software, TREND, Technical Note 1 (1993)

Diagnostics

• -23001, field line segment corrupted

• -23002, different B at the field line segment extremities

• -23003, invalid B along the field line segment

Common Blocks

• uc170 - temporary magnetic field line

• uc190 - control parameters, set 1

Dependencies

Called by

• ul220 - get information on a magnetic field line segment

• uf411 - search a local magnetic equator

• uf415 - rebuild the labels of the field line

Calls

None

See also

• ul240 - evaluate the Hilton’s function

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

Reported Bugs

None

Examples

None

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UNILIB/tags/v3.03