Chapter 1. Theory

Chapter 2. Computational details

REFERENCES

2.1 The singular vector code

2.1.1 Set-up routines

Table 2.1 Constants in namelist NAMLCZ controlling the singular vector computation.

NAME	TYPE	PURPOSE	DEFAULT
LANCZOS	LOGICAL	Activates singular vector computation with Lanczos algorithm (NCONF=601)	TRUE
LJACDAV	LOGICAL	Activates singular vector computations with Jacobi-Davidson algorithm (NCONF=131)	FALSE
LOCNORM	LOGICAL	Switch to localize norm computation in grid space	TRUE
ALAT1	REAL	NW corner of local area (defined by point 1)	30
ALON1	REAL		359.5
ALAT3	REAL	SE corner of local area (defined by point 3)	90
ALON3	REAL		0
NLEVMIN	INTEGER	Minimum level of local area	1
NLEVMAX	INTEGER	Maximum level of local area	NLEVG
LSPTRLC0	LOGICAL	Switch to truncate in spectral space at initial (0) time	FALSE
LSPTRLC1	LOGICAL	Switch to truncate in spectral space at final (1) time	FALSE
NWTRMIN0(1)	INTEGER	Spectral coefficients with total wavenumber outside window are set to zero	0
NWTRMAX0(1)	INTEGER		NXMAX
LNEWNORMT0	LOGICAL	Switch to re-define the norm at initial time	FALSE
NEWNORMT0	INTEGER	Re-defines initial norm 1: total energy 2: kinetic energy 3: vorticity squared 4: stream function squared 5: rotational kinetic energy	1
NITERL	INTEGER	Maximum number of Lanczos or Jacob-Davidson inner iterations	70
NINNER	INTEGER	Number of Jacobi-Davidson inner iterations	2
NJDSTOP	INTEGER	Value of NSTOP when LJACDAV=TRUE	144
LEVOLC	LOGICAL	Switch to evolve singular vectors	TRUE
NEIGEVO	INTEGER	Number of singular vectors to evolve	35
NLANTYPE	INTEGER	Determines type of singular vectors 1: energy type norms are used 2 and 3: obsolete 4: same as 1 but now NCONF = 131 5: Hessian is used at initial time 6: for computing eigensystem of the Hessian	1
The routine SULCZ defines the constants as listed in Table 2.1 and determines the configuration of the singular vector computation.

2.1.2 Main routines

(2.1)