mindspore.numpy.std(x, axis=None, ddof=0, keepdims=False)[source]

Computes the standard deviation along the specified axis. The standard deviation is the square root of the average of the squared deviations from the mean, i.e., \(std = sqrt(mean(abs(x - x.mean())**2))\).

Returns the standard deviation, which is computed for the flattened array by default, otherwise over the specified axis.


Numpy arguments dtype, out and where are not supported.

  • x (Tensor) – A Tensor to be calculated.

  • axis (Union[None, int, tuple(int)]) –

    Axis or axes along which the standard deviation is computed. Default: None.

    If None, compute the standard deviation of the flattened array.

  • ddof (int) – Means Delta Degrees of Freedom. The divisor used in calculations is \(N - ddof\), where \(N\) represents the number of elements. Default: 0.

  • keepdims – Default: False.


Standard deviation tensor.

Supported Platforms:

Ascend GPU CPU


>>> import mindspore.numpy as np
>>> input_x = np.array([1., 2., 3., 4.])
>>> output = np.std(input_x)
>>> print(output)