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Log

Synopsis​

This operator stores information into the log table. This information can be almost anything including parameter values of operators, apply-count of operators, execution time etc. The stored information can be plotted by the GUI when the process execution is complete. Moreover, the information can also be written into a file.

Description​

The Log operator is mostly used when you want to see the values calculated during the execution of the process that are otherwise not visible. For example you want to see values of different parameters in all iterations of any Loop operator. In such scenarios the ideal operator is the Log operator. A large variety of information can be stored using this operator. Values of all parameters of all operators in the current process can be stored. Other information like apply-count, cpu-time, execution-time, loop-time etc can also be stored. The information stored in the log table can be viewed in the Results View. The information can also be analyzed in form of various graphs using the Plot View in the Results Workspace. The information can also be written directly into a file using the filename parameter.

The log parameter is used for specifying the information to be stored. The column name option specifies the name of the column in the log table (and/or file). Then you can select any operator from the drop down menu. Once you have selected an operator, you have two choices. You can either store a parameter value or store other values. If you opt for the parameter value, you can choose any parameter of the selected operator through the drop down menu. If you opt for other values, you can choose any value like apply-count, cpu-time etc from the last drop down menu.

Each time the Log operator is applied, all the values and parameters specified by the log parameter are collected and stored in a data row. When the process finishes, the operator writes the collected data rows into a file (if the filename parameter has a valid path). In GUI mode, 2D or 3D plots are automatically generated and displayed in the Results Workspace. Please study the attached Example Processes to understand working of this operator.

Input​

through​

It is not compulsory to connect any object with this port. Any object connected at this port is delivered without any modifications to the output port. This operator can have multiple inputs. When one input is connected, another through input port becomes available which is ready to accept another input (if any). The order of inputs remains the same. The object supplied at the first through input port of the Log operator is available at the first through output port.

Output​

through​

The objects that were given as input are passed without changing to the output through this port. It is not compulsory to attach this port to any other port. The Log operator can have multiple outputs. When one output is connected, another through output port becomes available which is ready to deliver another output (if any). The order of outputs remains the same. The object delivered at the first through input port of the Log operator is delivered at the first through output port

Parameters​

Filename​

This parameter is used if you want to write the stored values into a file. The path of the file is specified here.

Log​

This is the most important parameter of this operator. It is used for specifying the values that should be stored by the Log operator. The log parameter is used for specifying the information to be stored. The column name option specifies the name of the column in the log table (and/or file). Then you can select any operator from the drop down menu. Once you have selected an operator, you have two choices. You can either store a parameter value or store other values. If you opt for the parameter value, you can choose any parameter of the selected operator through the drop down menu. If you opt for other values, you can choose any value like apply-count, cpu-time etc from the last drop down menu.

Sorting type​

This parameter indicates if the logged values should be sorted according to the specified dimension.

Sorting dimension​

This parameter is only available when the sorting type parameter is set to 'top-k' or 'bottom-k'. This parameter is used for specifying the dimension that is to be used for sorting.

Sorting k​

This parameter is only available when the sorting type parameter is set to 'top-k' or 'bottom-k'. Only k results will be kept.

Persistent​

This is an expert parameter. This parameter indicates if the results should be written to the specified file immediately.