Ishigami Function (Connector)

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This page shows how to connect the third party solver of Ishigami Function to COSSAN-X.

Problem Definition in COSSAN-X

Create a new project as discussed in Cantilever Beam (Uncertainty Quantification), and name it 'Ishigami_function'. Then, add 2 parameters a and b and 3 random variables x1, x2 and x3 as defined in Ishigami Function.


In this tutorial, the evaluator contains a single black-box model of type connector. Before creating a black box model it is necessary to create a connector configuration

Connector Configuration

The following steps are required to set up the connection configuration to the Ishigami solver:

  • Click on 'Window' -> 'Preferences', then select 'Connectors' and 'Add...'
  • In 'Name:' set configuration_ishigami
  • In 'Connector type' select 'User defined'
  • Leave 'Use Remote Solver?' unchecked
  • In 'Solver Binary Path', browse for the location where the solver ishigamiFunction previously compiled is located
  • Leave 'Execution Flag:' and 'Execution Command:' as predefined
Connector ishigami configuration.png


Add a new connector named 'connector_ishigami'. Select the previoulsy defined configuration from the dropdown menu.

Connector ishigami creation.png

Import the files input.dat and result.out from OpenSourceSoftware/src/ishigamiFunction by using 'Import File...'


 ; Ishigami function inputs for a single run
 version = 0.01  
 [parameters]          ; Parameters of the Ishigami function
 a =   7.0000e+00              
 b =   5.0000e-02 
 [inputs]			  ; Random input value
 x1 =   0.0000e+00
 x2 =   0.0000e+00
 x3 =   0.0000e+00


Connector ishigami with imported files.png

Select 'input.dat' as main input file, and select the check-box next to it in the box injector to instruct COSSAN-X that the file will be modified by inserting sampled data into it. Finally, add 'result.out' as a output file.

Connector ishigami with injext.png


Create the relevant insertion points for the parameters a and b and the random variables X1, X2 and X3, by selecting the numerical value already existing in the input file, right click on it and select 'Connect to...'.

Be sure that the format is '%10.4e' for all the identifiers. To change the properties, right-click on the identifier, select 'Identifier Properties...' and change 'Format'.

Connector ishigami injector.png


Create an anchor point by selecting 'Result ', right click and 'Add Anchor'.

Create a response by selecting the numerical value listed under 'Result', right click and 'Add Response'. Set the response name to 'out'.

Finally, from the outline on the right, drag the response 'out' on the anchor to create a link between anchor and response.

Connector ishigami extractor.png

Model and Analysis

Add 'connector_ishigami' to a new model. You can now run an analysis with the external software as explained in Cantilever Beam (Uncertainty Quantification).

See Also

Ishigami Function