## DEV Community

Super Kai (Kazuya Ito)

Posted on • Updated on

# float_power() in PyTorch

*My post explains square() and pow().

float_power() can get the 0D or more D tensor of the zero or more powers of `float` or `complex` from two of the 0D or more D tensors of zero or more elements or the 0D or more D tensor of zero or more elements and a scalar as shown below:

*Memos:

• `float_power()` can be used with torch or a tensor.
• The 1st argument(`input`) with `torch`(Type:`tensor` or `scalar` of `int`, `float`, `complex` or `bool`) or using a tensor(Type:`tensor` of `int`, `float`, `complex` or `bool`)(Required). *`torch` must use a scalar without `input=`.
• The 2nd argument with `torch` or the 1st argument with a tensor is `exponent`(Required-Type:`tensor` or `scalar` of `int`, `float`, `complex` or `bool`).
• There is `out` argument with `torch`(Optional-Type:`tensor`): *Memos:
• `out=` must be used.
• My post explains `out` argument.
• The combination of a scalar(`input` or a tensor) and a scalar(`exponent`) cannot be used.
``````import torch

tensor1 = torch.tensor(-3.)
tensor2 = torch.tensor([-4., -3., -2., -1., 0., 1., 2., 3.])

torch.float_power(input=tensor1, exponent=tensor2)
tensor1.float_power(exponent=tensor2)
# tensor([1.2346e-02, -3.7037e-02, 1.1111e-01, -3.3333e-01,
#         1.0000e+00, -3.0000e+00, 9.0000e+00, -2.7000e+01],
#        dtype=torch.float64)

torch.float_power(-3., exponent=tensor2)
# tensor([1.2346e-02, -3.7037e-02, 1.1111e-01, -3.3333e-01,
#         1.0000e+00, -3.0000e+00, 9.0000e+00, -2.7000e+01],
#        dtype=torch.float64)

torch.float_power(input=tensor1, exponent=-3.)
# tensor(-0.0370, dtype=torch.float64)

tensor1 = torch.tensor([-3., 1., -2., 3., 5., -5., 0., -4.])
tensor2 = torch.tensor([-4., -3., -2., -1., 0., 1., 2., 3.])

torch.float_power(input=tensor1, exponent=tensor2)
# tensor([1.2346e-02, 1.0000e+00, 2.5000e-01, 3.3333e-01,
#         1.0000e+00, -5.0000e+00, 0.0000e+00, -6.4000e+01],
#        dtype=torch.float64)

torch.float_power(-3., exponent=tensor2)
# tensor([1.2346e-02, -3.7037e-02, 1.1111e-01, -3.3333e-01,
#         1.0000e+00, -3.0000e+00, 9.0000e+00, -2.7000e+01],
#        dtype=torch.float64)

torch.float_power(input=tensor1, exponent=-3.)
# tensor([-0.0370, 1.0000, -0.1250, 0.0370,
#         0.0080, -0.0080, inf, -0.0156], dtype=torch.float64)

tensor1 = torch.tensor([[-3., 1., -2., 3.], [5., -5., 0., -4.]])
tensor2 = torch.tensor([0., 1., 2., 3.])

torch.float_power(input=tensor1, exponent=tensor2)
# tensor([[1., 1., 4., 27.], [1., -5., 0., -64.]],
#        dtype=torch.float64)

torch.float_power(-3., exponent=tensor2)
# tensor([1., -3., 9., -27.], dtype=torch.float64)

torch.float_power(input=tensor1, exponent=-3.)
# tensor([[-0.0370, 1.0000, -0.1250, 0.0370],
#         [0.0080, -0.0080, inf, -0.0156]],
#        dtype=torch.float64)

tensor1 = torch.tensor([[[-3., 1.], [-2., 3.]],
[[5., -5.], [0., -4.]]])
tensor2 = torch.tensor([2., 3.])

torch.float_power(input=tensor1, exponent=tensor2)
# tensor([[[9., 1.], [4., 27.]],
#         [[25., -125.], [0., -64.]]], dtype=torch.float64)

torch.float_power(-3., exponent=tensor2)
# tensor([9., -27.], dtype=torch.float64)

torch.float_power(input=tensor1, exponent=-3.)
# tensor([[[-0.0370, 1.0000], [-0.1250, 0.0370]],
#         [[0.0080, -0.0080], [inf, -0.0156]]],
#        dtype=torch.float64)

tensor1 = torch.tensor([[[-3, 1], [-2, 3]],
[[5, -5], [0, -4]]])
tensor2 = torch.tensor([2, 3])

torch.float_power(input=tensor1, exponent=tensor2)
# tensor([[[9., 1.], [4., 27.]],
#         [[25., -125.], [0., -64.]]], dtype=torch.float64)

torch.float_power(-3, exponent=tensor2)
# tensor([9., -27.], dtype=torch.float64)

torch.float_power(input=tensor1, exponent=-3)
# tensor([[[-0.0370, 1.0000], [-0.1250, 0.0370]],
#         [[0.0080, -0.0080], [inf, -0.0156]]],
#        dtype=torch.float64)

tensor1 = torch.tensor([[[-3.+0.j, 1.+0.j], [-2.+0.j, 3.+0.j]],
[[5.+0.j, -5.+0.j], [0.+0.j, -4.+0.j]]])
tensor2 = torch.tensor([2.+0.j, 3.+0.j])

torch.float_power(input=tensor1, exponent=tensor2)
# tensor([[[9.0000-2.2044e-15j, 1.0000+0.0000e+00j],
#          [4.0000-9.7972e-16j, 27.0000+0.0000e+00j]],
#         [[25.0000+0.0000e+00j, -125.0000+4.5924e-14j],
#          [0.0000-0.0000e+00j, -64.0000+2.3513e-14j]]],
#        dtype=torch.complex128)

torch.float_power(-3.+0.j, exponent=tensor2)
# tensor([9.0000-2.2044e-15j, -27.0000+9.9196e-15j],
#        dtype=torch.complex128)

torch.float_power(input=tensor1, exponent=-3.+0.j)
# tensor([[[-0.0370-1.3607e-17j, 1.0000+0.0000e+00j],
#          [-0.1250-4.5924e-17j, 0.0370+0.0000e+00j]],
#         [[0.0080+0.0000e+00j, -0.0080-2.9392e-18j],
#          [inf+nanj, -0.0156-5.7405e-18j]]],
#        dtype=torch.complex128)

tensor1 = torch.tensor([[[True, False], [True, False]],
[[False, True], [False, True]]])
tensor2 = torch.tensor([True, False])

torch.float_power(input=tensor1, exponent=tensor2)
# tensor([[[1., 1.], [1., 1.]],
#         [[0., 1.], [0., 1.]]], dtype=torch.float64)

torch.float_power(True, exponent=tensor2)
# tensor([1., 1.], dtype=torch.float64)

torch.float_power(input=tensor1, exponent=True)
# tensor([[[1., 0.], [1., 0.]],
#         [[0., 1.], [0., 1.]]], dtype=torch.float64)
``````