COMSOL 6.3

Table 6-28: Valid AWE Properties.
Property	Value	Default	Description
acceptshort	on \| off	on	If on, the solver accepts short intervals unconditionally.
atol	scalar	0.001	Absolute tolerance for parameter sweep.
aweassemble	all \| one	all	Either assemble all the needed matrices at once, or one at a time.
awefunc	String \| vector of strings		Expression(s) used in the search algorithm.
clist	String array		Provide values for constants as input parameters using a string array; for the corresponding constant names, use cname. See The clist and cname Properties.
cname	String array		Provide names of constants as input parameters using a string array; for the corresponding constant values, use clist. See The clist and cname Properties.
control	String	user	Name of controlling study step.
expeval	scalar \| numeric vector	range(0.1,0.1,0.9)	Where to check the error in each subinterval.
expsize	scalar	3	Number of terms in expansion.
exptype	pade \| taylor	pade	Use Padé or Taylor expansions to approximate the unknown.
keeplog	on \| off	off	Keep warnings in stored log.
linearity	false \| linper	false	Use linear linearity or a linear perturbation.
linplistsolnum	integer array	new int[]{1}	List of solutions to use for the linearization point, when linpsolnum is set to from_list.
linpmanualsolnum	solution number	new int[]{1}	Solution number (index) to use for the linearization point, when linpsolnum is set to manual.
linpmethod	sol \| init	init	Method used for linearization point, which for sol is given by the linpsol property.
linpsol	zero \| solution object	zero	Linearization point solution.
linpsolnum	all \| auto \| first \| last \| from_list \| interp \| manual \| solution number	auto	Indices to solutions to use as linearization points. The default value from a default solver is case dependent.
linpsoluse	current \| manual \| solution store tag	current	Linearization point solution to use.
linpsolusesolnum	integer		Index for the solution to use when linpsoluse is set to manual.
linpt	double	0	Interpolated point for the linearization point when linpsolnum is set to interp.
minint	scalar	0	The shortest allowed subinterval length.
minintactive	on \| off	off	If off, rtol times the parameter span is used. If on, minint is used.
message	String		The log message from the last solution process.
output	solution \| rom	solution	Output the solution or a reduced-order model.
outsollinearized	du \| u	du	Store the total solution (u) or deviation and linearization point (du), when storelinpoint is set to off.
plist	scalar \| numeric vector		Parameter list.
plot	on \| off	off	Plot while solving.
plotgroup	String	default	Plot group to use for plot while solving.
pname	vector of strings		Parameter names.
pout	plist \| psteps	plist	When pout is set to plist, output solutions for the parameters in plist. When pout is set to psteps, output solutions at the parameter values chosen by the solver, which will coincide with the adaptively found expansion points.
probesel	all \| none \| manual	all	The probes to compute.
probes	vector of strings		Probes to use when probesel=manual.
romdata	String	new	Tag of the target container for the reduced model (new for a new reduced model), when output is set to rom.
rtol	scalar	0.01	Relative tolerance for parameter sweep.
storelinpoint	on \| off	off	Whether to store the linearization point.

Table 6-28: Valid AWE Properties.

Property

Value

Default

Description

acceptshort

on | off

If on, the solver accepts short intervals unconditionally.

atol

scalar

0.001

Absolute tolerance for parameter sweep.

aweassemble

all | one

all

Either assemble all the needed matrices at once, or one at a time.

awefunc

String | vector of strings

Expression(s) used in the search algorithm.

clist

String array

Provide values for constants as input parameters using a string array; for the corresponding constant names, use cname. See The clist and cname Properties.

cname

String array

Provide names of constants as input parameters using a string array; for the corresponding constant values, use clist. See The clist and cname Properties.

control

String

user

Name of controlling study step.

expeval

scalar | numeric vector

range(0.1,0.1,0.9)

Where to check the error in each subinterval.

expsize

scalar

Number of terms in expansion.

exptype

pade | taylor

pade

Use Padé or Taylor expansions to approximate the unknown.

keeplog

on | off

off

Keep warnings in stored log.

linearity

false | linper

false

Use linear linearity or a linear perturbation.

linplistsolnum

integer array

new int[]{1}

List of solutions to use for the linearization point, when linpsolnum is set to from_list.

linpmanualsolnum

solution number

new int[]{1}

Solution number (index) to use for the linearization point, when linpsolnum is set to manual.

linpmethod

sol | init

init

Method used for linearization point, which for sol is given by the linpsol property.

linpsol

zero | solution object

zero

Linearization point solution.

linpsolnum

auto

Indices to solutions to use as linearization points. The default value from a default solver is case dependent.

linpsoluse

current | manual | solution store tag

current

Linearization point solution to use.

linpsolusesolnum

integer

Index for the solution to use when linpsoluse is set to manual.

linpt

double

Interpolated point for the linearization point when linpsolnum is set to interp.

minint

scalar

The shortest allowed subinterval length.

minintactive

on | off

off

If off, rtol times the parameter span is used. If on, minint is used.

message

String

The log message from the last solution process.

output

solution | rom

solution

Output the solution or a reduced-order model.

outsollinearized

du | u

Store the total solution (u) or deviation and linearization point (du), when storelinpoint is set to off.

plist

scalar | numeric vector

on | off

Plot group to use for plot while solving.

plist | psteps

When pout is set to plist, output solutions for the parameters in plist. When pout is set to psteps, output solutions at the parameter values chosen by the solver, which will coincide with the adaptively found expansion points.

probesel

all | none | manual

all

The probes to compute.

probes

vector of strings

Probes to use when probesel=manual.

romdata

String

new

Tag of the target container for the reduced model (new for a new reduced model), when output is set to rom.

rtol

scalar

0.01

Relative tolerance for parameter sweep.

storelinpoint

on | off

off

Whether to store the linearization point.

The AWE solver computes expansions of an underlying problem around certain parameter values. In the first step the largest and smallest values of plist are used as expansion points. Using these expansions, the values of one or more functions at intermediate parameter values are computed. If the two expansions give similar enough functional values at these internal points, the interval is accepted and no subdivisions of that particular interval are deemed necessary.

The property awefunc is used to specify the functionals of interest, and the property expeval determines at which internal points these functionals are to be evaluated. The values for expeval are given relative the interval. That is, a value of 0.5 means that the functionals are evaluated at the midpoint of each interval. When the functional values from the two expansions are compared, a check is performed to see if they fulfill the specified tolerances atol and rtol. If neither of the tolerances are fulfilled, the interval is bisected, and the process is repeated for each subinterval. Before a bisection is performed a check is made to make sure that the new intervals are not shorter than the shortest allowed. By default the shortest allowed interval is given by the relative tolerance times the length of the interval defined by plist (when minintactive is set to off). If minintactive has been set to on the value of minint is the shortest interval allowed. If minint has been specified, the value of minintactive is on by default. The property acceptshort determines how to handle too short intervals. If acceptshort is set to off and a short interval is detected, the solver is interrupted with an error/warning. If acceptshort is set to on and a short interval is detected, the solver accepts the interval even if the tolerances have not been fulfilled.

In AWE several matrices are needed to compute each expansion. There are two options when it comes to assembling these matrices: With aweassemble set to all everything is assembled in a single call to the Xmesh. With aweassemble set to one, the matrices are assembled one at a time. The first option is faster but requires more memory.