PythonExecutioner (deeplearning4j 1.0.0-beta6 API)

java.lang.Object
- org.datavec.python.PythonExecutioner

```
public class PythonExecutioner
extends Object
```
Allows execution of python scripts managed by an internal interpreter. An end user may specify a python script to run via any of the execution methods available in this class. At static initialization time (when the class is first initialized) a number of components are setup: 1. The python path. A user may over ride this with the system property DEFAULT_PYTHON_PATH_PROPERTY 2. Since this executioner uses javacpp to manage and run python interpreters underneath the covers, a user may also over ride the system property JAVACPP_PYTHON_APPEND_TYPE with one of the PythonExecutioner.JavaCppPathType values. This will allow the user to determine whether the javacpp default python path is used at all, and if so whether it is appended, prepended, or not used. This behavior is useful when you need to use an external python distribution such as anaconda. 3. A main interpreter: This is the default interpreter to be used with the main thread. We may initialize one or more relative to the thread invoking the python code. 4. A proper numpy import for use with javacpp: We call numpy import ourselves to ensure proper loading of native libraries needed by numpy are allowed to load in the proper order. If we don't do this, it causes a variety of issues with running numpy. 5. Various python scripts pre defined on the classpath included right with the java code. These are auxillary python scripts used for loading classes, pre defining certain kinds of behavior in order for us to manipulate values within the python memory, as well as pulling them out of memory for integration within the internal python executioner. You can see this behavior in _readOutputs(PythonVariables) as an example. For more information on how this works, please take a look at the init() method. Generally, a user defining a python script for use by the python executioner will have a set of defined target input values and output values. These values should not be present when actually running the script, but just referenced. In order to test your python script for execution outside the engine, we recommend commenting out a few default values as dummy input values. This will allow an end user to test their script before trying to use the server. In order to get output values out of a python script, all a user has to do is define the output variables they want being used in the final output in the actual pipeline. For example, if a user wants to return a dictionary, they just have to create a dictionary with that name and based on the configured PythonVariables passed as outputs to one of the execution methods, we can pull the values out automatically. For input definitions, it is similar. You just define the values you want used in PythonVariables and we will automatically generate code for defining those values as desired for running. This allows the user to customize values dynamically at runtime but reference them by name in a python script.

Author:

Fariz Rahman, Adam Gibson

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class PythonExecutioner.JavaCppPathType
One of a few desired values for how we should handle using javacpp's python path.

Nested Classes
Modifier and Type	Class and Description
`static class`	`PythonExecutioner.JavaCppPathType` One of a few desired values for how we should handle using javacpp's python path.

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`ALL_VARIABLES_KEY`
`static String`	`DEFAULT_APPEND_TYPE`
`static String`	`DEFAULT_PYTHON_PATH_PROPERTY`
`static String`	`JAVACPP_PYTHON_APPEND_TYPE`
`static String`	`MAIN_INTERPRETER_NAME`

Constructor Summary

Constructors
Constructor and Description

PythonExecutioner()

Constructors
Constructor and Description
`PythonExecutioner()`

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static void`	`clearNonMainInterpreters()` Clear the non main intrepreters.
`static PythonVariables`	`defaultPythonVariableOutput()`
`static void`	`deleteInterpreter(String interpreterName)`
`static Map`	`evalDict(String varName)` Evaluate a string based on the current variable name.
`static Double`	`evalFloat(String varName)` Evaluate a string based on the current variable name.
`static long`	`evalInteger(String varName)` Evaluate a string based on the current variable name.
`static Object[]`	`evalList(String varName)` Evaluate a string based on the current variable name.
`static NumpyArray`	`evalNdArray(String varName)` Evaluate a string based on the current variable name.
`static String`	`evalString(String varName)` Evaluate a string based on the current variable name.
`static PythonVariables`	`exec(PythonTransform transform, PythonVariables inputs)` Run a `PythonTransform` with the given inputs
`static void`	`exec(String code)` Executes python code.
`static void`	`exec(String code, PythonVariables pyOutputs)` Run the given code with the given python outputs
`static void`	`exec(String code, PythonVariables pyInputs, PythonVariables pyOutputs)` Execute the given python code with the given `PythonVariables` as inputs and outputs
`static PythonVariables`	`execAndReturnAllVariables(String code)` Run the code and return the outputs
`static PythonVariables`	`execAndReturnAllVariables(String code, PythonVariables pyInputs)`
`static PythonVariables`	`execWithSetupAndRun(PythonTransform transform, PythonVariables inputs)`
`static void`	`execWithSetupAndRun(String code)` Executes python code and looks for methods setup() and run() If both setup() and run() are found, both are executed for the first time and for subsequent calls only run() is executed.
`static void`	`execWithSetupAndRun(String code, PythonVariables pyOutputs)` Executes python code and looks for methods setup() and run() If both setup() and run() are found, both are executed for the first time and for subsequent calls only run() is executed.
`static void`	`execWithSetupAndRun(String code, PythonVariables pyInputs, PythonVariables pyOutputs)` Execute the given python code with the `PythonVariables` inputs and outputs for storing the values specified by the user and needed by the user as output
`static PythonVariables`	`execWithSetupRunAndReturnAllVariables(String code)`
`static PythonVariables`	`execWithSetupRunAndReturnAllVariables(String code, PythonVariables pyInputs)`
`static String`	`getInterpreter()` Returns the current interpreter.
`static String`	`getPythonPath()` Return the python path being used.
`static boolean`	`hasInterpreter(String interpreterName)`
`static void`	`init()` Initialize the name space and the python execution Calling this method more than once will be a no op
`static void`	`printPythonVersion()` Print the python version to standard out.
`static void`	`resetAllInterpreters()` Run `resetInterpreter(String)` on all interpreters.
`static void`	`resetInterpreter(String interpreterName)` Reset the interpreter with the given name.
`static void`	`resetMainInterpreter()` Reset the main interpreter.
`static void`	`setInterpreter(String interpreterName)`
`static void`	`setPythonPath()` Set the python path.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - DEFAULT_PYTHON_PATH_PROPERTY
```
public static final String DEFAULT_PYTHON_PATH_PROPERTY
```
    See Also:
    
    Constant Field Values
  - JAVACPP_PYTHON_APPEND_TYPE
```
public static final String JAVACPP_PYTHON_APPEND_TYPE
```
    See Also:
    
    Constant Field Values
  - DEFAULT_APPEND_TYPE
```
public static final String DEFAULT_APPEND_TYPE
```
    See Also:
    
    Constant Field Values
  - ALL_VARIABLES_KEY
```
public static final String ALL_VARIABLES_KEY
```
    See Also:
    
    Constant Field Values
  - MAIN_INTERPRETER_NAME
```
public static final String MAIN_INTERPRETER_NAME
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - PythonExecutioner
```
public PythonExecutioner()
```
- Method Detail
  - setPythonPath
```
public static void setPythonPath()
```
    Set the python path. Generally you can just use the PYTHONPATH environment variable, but if you need to set it from code, this can work as well.
  - init
```
public static void init()
```
    Initialize the name space and the python execution Calling this method more than once will be a no op
  - resetAllInterpreters
```
public static void resetAllInterpreters()
```
    Run resetInterpreter(String) on all interpreters.
  - resetMainInterpreter
```
public static void resetMainInterpreter()
```
    Reset the main interpreter. For more information see resetInterpreter(String)
  - resetInterpreter
```
public static void resetInterpreter(String interpreterName)
```
    Reset the interpreter with the given name. Runs pythonexec/clear_vars.py For more information see: https://stackoverflow.com/questions/3543833/how-do-i-clear-all-variables-in-the-middle-of-a-python-script
    
    Parameters:
    
    interpreterName - the interpreter name to reset
  - clearNonMainInterpreters
```
public static void clearNonMainInterpreters()
```
    Clear the non main intrepreters.
  - defaultPythonVariableOutput
```
public static PythonVariables defaultPythonVariableOutput()
```
  - getPythonPath
```
public static String getPythonPath()
```
    Return the python path being used.
    
    Returns:
    
    a string specifying the python path in use
  - setInterpreter
```
public static void setInterpreter(String interpreterName)
```
  - getInterpreter
```
public static String getInterpreter()
```
    Returns the current interpreter.
    
    Returns:
  - hasInterpreter
```
public static boolean hasInterpreter(String interpreterName)
```
  - deleteInterpreter
```
public static void deleteInterpreter(String interpreterName)
```
  - printPythonVersion
```
public static void printPythonVersion()
```
    Print the python version to standard out.
  - exec
```
public static void exec(String code)
```
    Executes python code. Also manages python thread state.
    
    Parameters:
    
    code - the code to run
  - execWithSetupAndRun
```
public static void execWithSetupAndRun(String code)
```
    Executes python code and looks for methods setup() and run() If both setup() and run() are found, both are executed for the first time and for subsequent calls only run() is executed.
  - execWithSetupAndRun
```
public static void execWithSetupAndRun(String code,
                                       PythonVariables pyOutputs)
```
    Executes python code and looks for methods setup() and run() If both setup() and run() are found, both are executed for the first time and for subsequent calls only run() is executed.
  - exec
```
public static void exec(String code,
                        PythonVariables pyOutputs)
```
    Run the given code with the given python outputs
    
    Parameters:
    
    code - the code to run
    
    pyOutputs - the outputs to run
  - exec
```
public static void exec(String code,
                        PythonVariables pyInputs,
                        PythonVariables pyOutputs)
                 throws Exception
```
    Execute the given python code with the given PythonVariables as inputs and outputs
    
    Parameters:
    
    code - the code to run
    
    pyInputs - the inputs to the code
    
    pyOutputs - the outputs to the code
    
    Throws:
    
    Exception
  - execWithSetupAndRun
```
public static void execWithSetupAndRun(String code,
                                       PythonVariables pyInputs,
                                       PythonVariables pyOutputs)
                                throws Exception
```
    Execute the given python code with the PythonVariables inputs and outputs for storing the values specified by the user and needed by the user as output
    
    Parameters:
    
    code - the python code to execute
    
    pyInputs - the python variables input in to the python script
    
    pyOutputs - the python variables output returned by the python script
    
    Throws:
    
    Exception
  - exec
```
public static PythonVariables exec(PythonTransform transform,
                                   PythonVariables inputs)
                            throws Exception
```
    Run a PythonTransform with the given inputs
    
    Parameters:
    
    transform - the transform to run
    
    inputs - the inputs to the transform
    
    Returns:
    
    the output variables
    
    Throws:
    
    Exception
  - execWithSetupAndRun
```
public static PythonVariables execWithSetupAndRun(PythonTransform transform,
                                                  PythonVariables inputs)
                                           throws Exception
```
    Throws:
    
    Exception
  - execAndReturnAllVariables
```
public static PythonVariables execAndReturnAllVariables(String code)
```
    Run the code and return the outputs
    
    Parameters:
    
    code - the code to run
    
    Returns:
    
    all python variables
  - execWithSetupRunAndReturnAllVariables
```
public static PythonVariables execWithSetupRunAndReturnAllVariables(String code)
```
  - execAndReturnAllVariables
```
public static PythonVariables execAndReturnAllVariables(String code,
                                                        PythonVariables pyInputs)
                                                 throws Exception
```
    Parameters:
    
    code - code string to run
    
    pyInputs - python input variables
    
    Returns:
    
    all python variables
    
    Throws:
    
    Exception - throws when there's an issue while execution of python code
  - execWithSetupRunAndReturnAllVariables
```
public static PythonVariables execWithSetupRunAndReturnAllVariables(String code,
                                                                    PythonVariables pyInputs)
                                                             throws Exception
```
    Throws:
    
    Exception
  - evalString
```
public static String evalString(String varName)
```
    Evaluate a string based on the current variable name. This variable named needs to be present or defined earlier in python code in order to pull out the values.
    
    Parameters:
    
    varName - the variable name to evaluate
    
    Returns:
    
    the evaluated value
  - evalInteger
```
public static long evalInteger(String varName)
```
    Evaluate a string based on the current variable name. This variable named needs to be present or defined earlier in python code in order to pull out the values.
    
    Parameters:
    
    varName - the variable name to evaluate
    
    Returns:
    
    the evaluated value
  - evalFloat
```
public static Double evalFloat(String varName)
```
    Evaluate a string based on the current variable name. This variable named needs to be present or defined earlier in python code in order to pull out the values.
    
    Parameters:
    
    varName - the variable name to evaluate
    
    Returns:
    
    the evaluated value
  - evalList
```
public static Object[] evalList(String varName)
```
    Evaluate a string based on the current variable name. This variable named needs to be present or defined earlier in python code in order to pull out the values.
    
    Parameters:
    
    varName - the variable name to evaluate
    
    Returns:
    
    the evaluated value
  - evalDict
```
public static Map evalDict(String varName)
```
    Evaluate a string based on the current variable name. This variable named needs to be present or defined earlier in python code in order to pull out the values.
    
    Parameters:
    
    varName - the variable name to evaluate
    
    Returns:
    
    the evaluated value
  - evalNdArray
```
public static NumpyArray evalNdArray(String varName)
```
    Evaluate a string based on the current variable name. This variable named needs to be present or defined earlier in python code in order to pull out the values.
    
    Parameters:
    
    varName - the variable name to evaluate
    
    Returns:
    
    the evaluated value

Class PythonExecutioner

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_PYTHON_PATH_PROPERTY

JAVACPP_PYTHON_APPEND_TYPE

DEFAULT_APPEND_TYPE

ALL_VARIABLES_KEY

MAIN_INTERPRETER_NAME

Constructor Detail

PythonExecutioner

Method Detail

setPythonPath

init

resetAllInterpreters

resetMainInterpreter

resetInterpreter

clearNonMainInterpreters

defaultPythonVariableOutput

getPythonPath

setInterpreter

getInterpreter

hasInterpreter

deleteInterpreter

printPythonVersion

exec

execWithSetupAndRun

execWithSetupAndRun

exec

exec

execWithSetupAndRun

exec

execWithSetupAndRun

execAndReturnAllVariables

execWithSetupRunAndReturnAllVariables

execAndReturnAllVariables

execWithSetupRunAndReturnAllVariables

evalString

evalInteger

evalFloat

evalList

evalDict

evalNdArray