### Navigation

- index
- modules |
- next |
- previous |
- NumPy v1.3 Manual (DRAFT) »
- NumPy Reference »
- Routines »
- Mathematical functions »

# numpy.sin

`numpy.``sin`(x[, out])

  Trigonometric sine, element-wise.

  Parameters: | x : array_like Angle, in radians ( rad equals 360 degrees).
  Returns: | y : array_like The sine of each element of x.

  See also

  `arcsin`, `sinh`, `cos`

  Notes

  The sine is one of the fundamental functions of trigonometry (the mathematical study of triangles). Consider a circle of radius 1 centered on the origin. A ray comes in from the axis, makes an angle at the origin (measured counter-clockwise from that axis), and departs from the origin. The coordinate of the outgoing ray’s intersection with the unit circle is the sine of that angle. It ranges from -1 for to +1 for The function has zeroes where the angle is a multiple of . Sines of angles between and are negative. The numerous properties of the sine and related functions are included in any standard trigonometry text.

  Examples

  Print sine of one angle:

      >>> np.sin(np.pi/2.)
      1.0

  Print sines of an array of angles given in degrees:

      >>> np.sin(np.array((0., 30., 45., 60., 90.)) * np.pi / 180. )
      array([ 0.        ,  0.5       ,  0.70710678,  0.8660254 ,  1.        ])

  Plot the sine function:

      >>> import matplotlib.pylab as plt
      >>> x = np.linspace(-np.pi, np.pi, 201)
      >>> plt.plot(x, np.sin(x))
      >>> plt.xlabel('Angle [rad]')
      >>> plt.ylabel('sin(x)')
      >>> plt.axis('tight')
      >>> plt.show()

### Navigation

- index
- modules |
- next |
- previous |
- NumPy v1.3 Manual (DRAFT) »
- NumPy Reference »
- Routines »
- Mathematical functions »