Configure INTERVAL-PROJECTION in Sherpa.
The Sherpa configuration variable (also called "state
object") sherpa.intproj contains settings of
INTERVAL-PROJECTION for plotting the fit statistic
as a function of parameter value, using the
PROJECTION algorithm in Sherpa.
See ahelp INTERVAL-PROJECTION for more details.
The sherpa.intproj fields are specified in the table:
| fast |
If 1, use a fast optimization algorithm
(LEVENBERG-MARQUARDT
or
SIMPLEX)
regardless of the current
METHOD.
If 0, use the current
METHOD. |
| expfac |
A multiplicative factor that expands the grid limits estimated by the
COVARIANCE
algorithm, if
the grid limits are determined automatically (see arange,
and below).
|
| arange |
If 1, the grid limits are to be determined automatically. If 0, the
grid limits are specified (see min and max).
|
| min |
Specifies the grid minimum.
This is always a linear quantity, regardless of the setting of
log (see below).
The setting is ignored if arange = 1.
|
| max |
Specifies the grid maximum.
This is always a linear quantity, regardless of the setting of
log (see below).
The setting is ignored if arange = 1.
|
| log |
Specifies whether to use a linear (0) or
logarithmic (1) spacing of grid points.
|
| nloop |
Specifies the number of grid points.
|
| sigma |
Specifies the number of sigma
(i.e., the change in statistic) for the plot.
|
To restore the default settings of the structure
at any time, use the Sherpa/S-Lang module function
restore_intproj.
List the current and default values of the intproj structure,
and restore the default values:
sherpa> sherpa.intproj.arange = 0
sherpa> sherpa.intproj.log = 1
sherpa> sherpa.intproj.sigma = 5
sherpa> list_intproj
Parameter Current Default Description
----------------------------------------------------------------------
fast 1 1 Switch to LM/simplex: 0(n)/1(y)
expfac 3 3 Expansion factor for grid
arange 0 1 Auto-range: 0(n)/1(y)
min 0 0 Minimum value
max 0 0 Maximum value
log 1 0 Log-spacing: 0(n)/1(y)
nloop 20 20 Number of grid points
sigma 5 1 Number of sigma
sherpa> restore_intproj
sherpa> list_intproj
Parameter Current Default Description
----------------------------------------------------------------------
fast 1 1 Switch to LM/simplex: 0(n)/1(y)
expfac 3 3 Expansion factor for grid
arange 1 1 Auto-range: 0(n)/1(y)
min 0 0 Minimum value
max 0 0 Maximum value
log 0 0 Log-spacing: 0(n)/1(y)
nloop 20 20 Number of grid points
sigma 1 1 Number of sigma
Create aliase for sherpa.intproj
sherpa> variable si = sherpa.intproj
sherpa> si.fast = 0
|
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