1*DECK FMAT
2      SUBROUTINE FMAT (X, Y, YP)
3C***BEGIN PROLOGUE  FMAT
4C***PURPOSE  Subsidiary to
5C***LIBRARY   SLATEC
6C***AUTHOR  (UNKNOWN)
7C***ROUTINES CALLED  (NONE)
8C***COMMON BLOCKS    SAVEX
9C***REVISION HISTORY  (YYMMDD)
10C   ??????  DATE WRITTEN
11C   891214  Prologue converted to Version 4.0 format.  (BAB)
12C***END PROLOGUE  FMAT
13      DIMENSION Y(*),YP(*)
14      COMMON /SAVEX/ XSAVE, TERM
15C***FIRST EXECUTABLE STATEMENT  FMAT
16      YP(1) = Y(2)
17      IF (X .EQ. XSAVE) GO TO 10
18      XSAVE=X
19      TANX=TAN(X/57.2957795130823)
20      TERM=3.0/TANX+2.0*TANX
21   10 YP(2) = -TERM*Y(2)-0.7*Y(1)
22      RETURN
23      END
24