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Dakota Reference Manual
Version 6.16
Explore and Predict with Confidence
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Samples variables as a specified values
This keyword is related to the topics:
Alias: none
Argument(s): none
Child Keywords:
| Required/Optional | Description of Group | Dakota Keyword | Dakota Keyword Description | |
|---|---|---|---|---|
| Required (Choose One) | Points Source (Group 1) | list_of_points | List of variable values to evaluate in a list parameter study | |
| import_points_file | File containing list of variable values to evaluate in a list parameter study | |||
| Optional | model_pointer | Identifier for model block to be used by a method | ||
Dakota's list parameter study allows for evaluations at user selected points of interest.
Default Behavior
By default, the list parameter study operates over all types of variables.
The number of real values in the list_of_points specification or file referenced by import_points_file must be a multiple of the total number of variables (including continuous and discrete types) contained in the variables specification.
Expected Outputs
A list parameter study produces a set of responses for each parameter set that is specified.
Expected HDF5 Output
If Dakota was built with HDF5 support and run with the hdf5 keyword, this method writes the following results to HDF5:
Usage Tips
n entries in the list), followed by the next parameter set (the next n entries), and so on, until the list of points has been exhausted. list_of_points keyword, discrete set values must be referred to using 0-based indexes, and not the values themselves. However, when using import_points_file, refer to discrete set values directly, not by index. list_of_points and import_points_file, Dakota expects the values for each evaluation to be ordered by type. The type ordering matches that of the variables section of this Reference Manual and of the listing in the Parameters file format section of the Dakota User's Manual [4]. When multiple variables are present for a single type, the ordering within that type must match the order specified by the user in the variables section of her input file.This shows the method and variables block of a Dakota input file that runs a list_parameter_study.
method
list_parameter_study
list_of_points =
3.1e6 0.0029 0.31
3.2e6 0.0028 0.32
3.3e6 0.0027 0.34
3.3e6 0.0026 0.36
variables
continuous_design = 3
descriptors = 'E' 'MASS' 'DENSITY'Note that because of the way Dakota treats whitespace, the above example is equivalent to:
method
list_parameter_study
list_of_points =
3.1e6 0.0029 0.31 3.2e6 0.0028
0.32 3.3e6 0.0027
0.34 3.3e6 0.0026 0.36
variables
continuous_design = 3
descriptors = 'E' 'MASS' 'DENSITY'
Although the first example is much more readable.
And here's a full input file:
# tested on Dakota 6.0 on 140501
environment
tabular_data
tabular_data_file 'List_param_study.dat'
method
list_parameter_study
list_of_points = 0.1 0.1
0.2 0.1
0.3 0.0
0.3 1.0
model
single
variables
active design
continuous_design = 2
descriptors 'x1' 'x2'
continuous_state = 1
descriptors = 'constant1'
initial_state = 100
interface
analysis_drivers 'text_book'
fork
asynchronous
evaluation_concurrency 2
responses
response_functions = 1
no_gradients
no_hessiansThis example illustrates the list_parameter_study.
evaluation_concurrency can be used active design is specified, this study will only iterate on the continuous_design variables.These keywords may also be of interest: