# xarray.ufuncs.arcsin

`xarray.ufuncs.``arcsin` = <xarray.ufuncs._UFuncDispatcher object>

  xarray specific variant of numpy.arcsin. Handles xarray.Dataset, xarray.DataArray, xarray.Variable, numpy.ndarray and dask.array.Array objects with automatic dispatching.

  Documentation from numpy:

  arcsin(x, /, out=None, *, where=True, casting=’same_kind’, order=’K’, dtype=None, subok=True[, signature, extobj])

  Inverse sine, element-wise.

  Parameters:

  x : array_like

  > y-coordinate on the unit circle.

  out : ndarray, None, or tuple of ndarray and None, optional

  > A location into which the result is stored. If provided, it must have a shape that the inputs broadcast to. If not provided or None, a freshly-allocated array is returned. A tuple (possible only as a keyword argument) must have length equal to the number of outputs.

  where : array_like, optional

  > Values of True indicate to calculate the ufunc at that position, values of False indicate to leave the value in the output alone.

  **kwargs

  > For other keyword-only arguments, see the ufunc docs.

  Returns:

  angle : ndarray

  > The inverse sine of each element in x, in radians and in the closed interval `[-pi/2, pi/2]`. If x is a scalar, a scalar is returned, otherwise an array.

  See also

  `sin`, `cos`, `arccos`, `tan`, `arctan`, `arctan2`, `emath.arcsin`

  Notes

  arcsin is a multivalued function: for each x there are infinitely many numbers z such that \(sin(z) = x\). The convention is to return the angle z whose real part lies in [-pi/2, pi/2].

  For real-valued input data types, arcsin always returns real output. For each value that cannot be expressed as a real number or infinity, it yields `nan` and sets the invalid floating point error flag.

  For complex-valued input, arcsin is a complex analytic function that has, by convention, the branch cuts [-inf, -1] and [1, inf] and is continuous from above on the former and from below on the latter.

  The inverse sine is also known as asin or sin^{-1}.

  References

  Abramowitz, M. and Stegun, I. A., Handbook of Mathematical Functions, 10th printing, New York: Dover, 1964, pp. 79ff. http://www.math.sfu.ca/~cbm/aands/

  Examples

      >>> np.arcsin(1)     # pi/2
      1.5707963267948966
      >>> np.arcsin(-1)    # -pi/2
      -1.5707963267948966
      >>> np.arcsin(0)
      0.0