Пример #1
0
def stateless_random_uniform(shape,
                             seed,
                             minval=0,
                             maxval=None,
                             dtype=dtypes.float32,
                             name=None):
  """Outputs deterministic pseudorandom values from a uniform distribution.

  This is a stateless version of `tf.random.uniform`: if run twice with the
  same seeds, it will produce the same pseudorandom numbers.  The output is
  consistent across multiple runs on the same hardware (and between CPU
  and GPU), but may change between versions of TensorFlow or on non-CPU/GPU
  hardware.

  The generated values follow a uniform distribution in the range
  `[minval, maxval)`. The lower bound `minval` is included in the range, while
  the upper bound `maxval` is excluded.

  For floats, the default range is `[0, 1)`.  For ints, at least `maxval` must
  be specified explicitly.

  In the integer case, the random integers are slightly biased unless
  `maxval - minval` is an exact power of two.  The bias is small for values of
  `maxval - minval` significantly smaller than the range of the output (either
  `2**32` or `2**64`).

  Args:
    shape: A 1-D integer Tensor or Python array. The shape of the output tensor.
    seed: A shape [2] integer Tensor of seeds to the random number generator.
    minval: A 0-D Tensor or Python value of type `dtype`. The lower bound on the
      range of random values to generate.  Defaults to 0.
    maxval: A 0-D Tensor or Python value of type `dtype`. The upper bound on the
      range of random values to generate.  Defaults to 1 if `dtype` is floating
      point.
    dtype: The type of the output: `float16`, `float32`, `float64`, `int32`, or
      `int64`.
    name: A name for the operation (optional).

  Returns:
    A tensor of the specified shape filled with random uniform values.

  Raises:
    ValueError: If `dtype` is integral and `maxval` is not specified.
  """
  dtype = dtypes.as_dtype(dtype)
  if dtype not in (dtypes.float16, dtypes.bfloat16, dtypes.float32,
                   dtypes.float64, dtypes.int32, dtypes.int64):
    raise ValueError("Invalid dtype %r" % dtype)
  if maxval is None:
    if dtype.is_integer:
      raise ValueError("Must specify maxval for integer dtype %r" % dtype)
    maxval = 1
  with ops.name_scope(name, "stateless_random_uniform",
                      [shape, seed, minval, maxval]) as name:
    shape = random_ops._ShapeTensor(shape)  # pylint: disable=protected-access
    minval = ops.convert_to_tensor(minval, dtype=dtype, name="min")
    maxval = ops.convert_to_tensor(maxval, dtype=dtype, name="max")
    if dtype.is_integer:
      return gen_stateless_random_ops.stateless_random_uniform_int(
          shape, seed=seed, minval=minval, maxval=maxval, name=name)
    else:
      rnd = gen_stateless_random_ops.stateless_random_uniform(
          shape, seed=seed, dtype=dtype)
      return math_ops.add(rnd * (maxval - minval), minval, name=name)
Пример #2
0
def stateless_random_uniform(shape,
                             seed,
                             minval=0,
                             maxval=None,
                             dtype=dtypes.float32,
                             name=None):
  """Outputs deterministic pseudorandom values from a uniform distribution.

  This is a stateless version of `tf.random.uniform`: if run twice with the
  same seeds, it will produce the same pseudorandom numbers.  The output is
  consistent across multiple runs on the same hardware (and between CPU
  and GPU), but may change between versions of TensorFlow or on non-CPU/GPU
  hardware.

  The generated values follow a uniform distribution in the range
  `[minval, maxval)`. The lower bound `minval` is included in the range, while
  the upper bound `maxval` is excluded.

  For floats, the default range is `[0, 1)`.  For ints, at least `maxval` must
  be specified explicitly.

  In the integer case, the random integers are slightly biased unless
  `maxval - minval` is an exact power of two.  The bias is small for values of
  `maxval - minval` significantly smaller than the range of the output (either
  `2**32` or `2**64`).

  For full-range (i.e. inclusive of both max and min) random integers, pass
  `minval=None` and `maxval=None` with an integer `dtype`. For an integer dtype
  either both `minval` and `maxval` must be `None` or neither may be `None`. For
  example:
  ```python
  ints = tf.random.stateless_uniform(
      [10], seed=(2, 3), minval=None, maxval=None, dtype=tf.int32)
  ```

  Args:
    shape: A 1-D integer Tensor or Python array. The shape of the output tensor.
    seed: A shape [2] Tensor, the seed to the random number generator. Must have
      dtype `int32` or `int64`. (When using XLA, only `int32` is allowed.)
    minval: A Tensor or Python value of type `dtype`, broadcastable with
      `shape` (for integer types, broadcasting is not supported, so it needs to
      be a scalar). The lower bound on the range of random values to
      generate. Pass `None` for full-range integers.  Defaults to 0.
    maxval: A Tensor or Python value of type `dtype`, broadcastable with
      `shape` (for integer types, broadcasting is not supported, so it needs to
      be a scalar). The upper bound on the range of random values to generate.
      Defaults to 1 if `dtype` is floating point. Pass `None` for full-range
      integers.
    dtype: The type of the output: `float16`, `float32`, `float64`, `int32`, or
      `int64`. For unbounded uniform ints (`minval`, `maxval` both `None`),
      `uint32` and `uint64` may be used.
    name: A name for the operation (optional).

  Returns:
    A tensor of the specified shape filled with random uniform values.

  Raises:
    ValueError: If `dtype` is integral and only one of `minval` or `maxval` is
      specified.
  """
  dtype = dtypes.as_dtype(dtype)
  if dtype not in (dtypes.float16, dtypes.bfloat16, dtypes.float32,
                   dtypes.float64, dtypes.int32, dtypes.int64, dtypes.uint32,
                   dtypes.uint64):
    raise ValueError("Invalid dtype %r" % dtype)
  if dtype.is_integer:
    if (minval is None) != (maxval is None):
      raise ValueError("For integer dtype {}, minval and maxval must be both "
                       "`None` or both non-`None`.".format(dtype))
    if minval is not None and dtype in (dtypes.uint32, dtypes.uint64):
      raise ValueError("Invalid dtype for bounded uniform integers: %r" % dtype)
  elif maxval is None:
    maxval = 1
  with ops.name_scope(name, "stateless_random_uniform",
                      [shape, seed, minval, maxval]) as name:
    shape = tensor_util.shape_tensor(shape)
    if dtype.is_integer and minval is None:
      result = gen_stateless_random_ops.stateless_random_uniform_full_int(
          shape, seed=seed, dtype=dtype, name=name)
    else:
      minval = ops.convert_to_tensor(minval, dtype=dtype, name="min")
      maxval = ops.convert_to_tensor(maxval, dtype=dtype, name="max")
      if dtype.is_integer:
        result = gen_stateless_random_ops.stateless_random_uniform_int(
            shape, seed=seed, minval=minval, maxval=maxval, name=name)
      else:
        rnd = gen_stateless_random_ops.stateless_random_uniform(
            shape, seed=seed, dtype=dtype)
        result = math_ops.add(rnd * (maxval - minval), minval, name=name)
    tensor_util.maybe_set_static_shape(result, shape)
    return result
Пример #3
0
def stateless_random_uniform(shape,
                             seed,
                             minval=0,
                             maxval=None,
                             dtype=dtypes.float32,
                             name=None):
  """Outputs deterministic pseudorandom values from a uniform distribution.

  This is a stateless version of `tf.random.uniform`: if run twice with the
  same seeds, it will produce the same pseudorandom numbers.  The output is
  consistent across multiple runs on the same hardware (and between CPU
  and GPU), but may change between versions of TensorFlow or on non-CPU/GPU
  hardware.

  The generated values follow a uniform distribution in the range
  `[minval, maxval)`. The lower bound `minval` is included in the range, while
  the upper bound `maxval` is excluded.

  For floats, the default range is `[0, 1)`.  For ints, at least `maxval` must
  be specified explicitly.

  In the integer case, the random integers are slightly biased unless
  `maxval - minval` is an exact power of two.  The bias is small for values of
  `maxval - minval` significantly smaller than the range of the output (either
  `2**32` or `2**64`).

  Args:
    shape: A 1-D integer Tensor or Python array. The shape of the output tensor.
    seed: A shape [2] integer Tensor of seeds to the random number generator.
    minval: A 0-D Tensor or Python value of type `dtype`. The lower bound on the
      range of random values to generate.  Defaults to 0.
    maxval: A 0-D Tensor or Python value of type `dtype`. The upper bound on the
      range of random values to generate.  Defaults to 1 if `dtype` is floating
      point.
    dtype: The type of the output: `float16`, `float32`, `float64`, `int32`, or
      `int64`.
    name: A name for the operation (optional).

  Returns:
    A tensor of the specified shape filled with random uniform values.

  Raises:
    ValueError: If `dtype` is integral and `maxval` is not specified.
  """
  dtype = dtypes.as_dtype(dtype)
  if dtype not in (dtypes.float16, dtypes.bfloat16, dtypes.float32,
                   dtypes.float64, dtypes.int32, dtypes.int64):
    raise ValueError("Invalid dtype %r" % dtype)
  if maxval is None:
    if dtype.is_integer:
      raise ValueError("Must specify maxval for integer dtype %r" % dtype)
    maxval = 1
  with ops.name_scope(name, "stateless_random_uniform",
                      [shape, seed, minval, maxval]) as name:
    shape = random_ops._ShapeTensor(shape)  # pylint: disable=protected-access
    minval = ops.convert_to_tensor(minval, dtype=dtype, name="min")
    maxval = ops.convert_to_tensor(maxval, dtype=dtype, name="max")
    if dtype.is_integer:
      return gen_stateless_random_ops.stateless_random_uniform_int(
          shape, seed=seed, minval=minval, maxval=maxval, name=name)
    else:
      rnd = gen_stateless_random_ops.stateless_random_uniform(
          shape, seed=seed, dtype=dtype)
      return math_ops.add(rnd * (maxval - minval), minval, name=name)