95 SUBROUTINE dlarrr( N, D, E, INFO )
106 DOUBLE PRECISION D( * ), E( * )
113 DOUBLE PRECISION ZERO, RELCOND
114 parameter ( zero = 0.0d0,
115 $ relcond = 0.999d0 )
120 DOUBLE PRECISION EPS, SAFMIN, SMLNUM, RMIN, TMP, TMP2,
125 DOUBLE PRECISION DLAMCH
136 safmin = dlamch(
'Safe minimum' )
137 eps = dlamch(
'Precision' )
138 smlnum = safmin / eps
139 rmin = sqrt( smlnum )
160 tmp = sqrt(abs(d(1)))
161 IF (tmp.LT.rmin) yesrel = .false.
162 IF(.NOT.yesrel)
GOTO 11
164 tmp2 = sqrt(abs(d(i)))
165 IF (tmp2.LT.rmin) yesrel = .false.
166 IF(.NOT.yesrel)
GOTO 11
167 offdig2 = abs(e(i-1))/(tmp*tmp2)
168 IF(offdig+offdig2.GE.relcond) yesrel = .false.
169 IF(.NOT.yesrel)
GOTO 11
subroutine dlarrr(N, D, E, INFO)
DLARRR performs tests to decide whether the symmetric tridiagonal matrix T warrants expensive computa...