MDI_ROLL(3)
NAME
mdi_roll -- MDI roll angle in degrees
SYNOPSIS
#include <soi_time.h>
#include <soi_ephem.h>
#include <soi_sds.h>
int mdi_roll (char *rolltable, TIME tobs, double *roll, TIME *tmod)
DESCRIPTION
mdi_roll() interpolates the tabulated MDI roll angles stored
in file rolltable to the requested observation time tobs.
The interpolated roll angle in degrees and the last modifi-
cation time of the table are returned in roll and tmod,
respectively.
FILES
~CM/tables/ephemeris/mdi_roll.raw
~CM/tables/ephemeris/mdi_roll.smooth
~CM/lib/_($MACH)/libastro.a
DIAGNOSTICS
Return values:
0 normal return
MDIROLL_CANT_READ_TABLE can't read table
MDIROLL_BAD_TABLE entries in table not time ordered
MDIROLL_CANT_INTERPOLATE requested time out of table range
Except in the case of normal return, roll and tmod are set
to MISSING.
BUGS
Does not extrapolate.
Always linearly interpolates.
Roll table is read on first call and cannot be changed on
subsequent calls.
AUTHOR
Keh-Cheng Chu
HISTORY
1999-01-13 SOI Version 2.1