Defined in tensorflow/contrib/training/python/training/

Parses hyperparameter values from a string into a python map.

values is a string containing comma-separated name=value pairs. For each pair, the value of the hyperparameter named name is set to value.

If a hyperparameter name appears multiple times in values, a ValueError is raised (e.g. 'a=1,a=2', 'a[1]=1,a[1]=2').

If a hyperparameter name in both an index assignment and scalar assignment, a ValueError is raised. (e.g. 'a=[1,2,3],a[0] = 1').

The value in name=value must follows the syntax according to the type of the parameter:

  • Scalar integer: A Python-parsable integer point value. E.g.: 1, 100, -12.
  • Scalar float: A Python-parsable floating point value. E.g.: 1.0, -.54e89.
  • Boolean: Either true or false.
  • Scalar string: A non-empty sequence of characters, excluding comma, spaces, and square brackets. E.g.: foo, bar_1.
  • List: A comma separated list of scalar values of the parameter type enclosed in square brackets. E.g.: [1,2,3], [1.0,1e-12], [high,low].

When index assignment is used, the corresponding type_map key should be the list name. E.g. for "arr[1]=0" the type_map must have the key "arr" (not "arr[1]").


  • values: String. Comma separated list of name=value pairs where 'value' must follow the syntax described above.
  • type_map: A dictionary mapping hyperparameter names to types. Note every parameter name in values must be a key in type_map. The values must conform to the types indicated, where a value V is said to conform to a type T if either V has type T, or V is a list of elements of type T. Hence, for a multidimensional parameter 'x' taking float values, 'x=[0.1,0.2]' will parse successfully if type_map['x'] = float.


A python map mapping each name to either: * A scalar value. * A list of scalar values. * A dictionary mapping index numbers to scalar values. (e.g. "x=5,L=[1,2],arr[1]=3" results in {'x':5,'L':[1,2],'arr':{1:3}}")


  • ValueError: If there is a problem with input.
    • If values cannot be parsed.
    • If a list is assigned to a list index (e.g. 'a[1] = [1,2,3]').
    • If the same rvalue is assigned two different values (e.g. 'a=1,a=2', 'a[1]=1,a[1]=2', or 'a=1,a=[1]')