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- Convolution and filtering (`astropy.convolution`) »
- Tophat2DKernel

# Tophat2DKernel

class `astropy.convolution.kernels.``Tophat2DKernel`(radius, **kwargs)

  Bases: `astropy.convolution.core.Kernel2D`

  2D Tophat filter kernel.

  The Tophat filter is an isotropic smoothing filter. It can produce artifact, when applied repeatedly on the same data.

  Parameters:

  radius : int

  > Radius of the filter kernel.

  mode : str, optional

  > One of the following discretization modes:
  >   - ‘center’ (default)

  >       Discretize model by taking the value at the center of the bin.

  >   - ‘linear_interp’

  >       Discretize model by performing a bilinear interpolation between the values at the corners of the bin.

  >   - ‘oversample’

  >       Discretize model by taking the average on an oversampled grid.

  >   - ‘integrate’

  >       Discretize model by integrating the model over the bin.

  factor : number, optional

  > Factor of oversampling. Default factor = 10.

  See also

  `Box2DKernel`, `Tophat2DKernel`, `MexicanHat2DKernel`, `Ring2DKernel`, `TrapezoidDisk2DKernel`, `AiryDisk2DKernel`

  Examples

  Kernel response:

  >     import matplotlib.pyplot as plt
  >     from astropy.convolution import Tophat2DKernel
  >     tophat_2D_kernel = Tophat2DKernel(40)
  >     plt.imshow(tophat_2D_kernel, interpolation='none', origin='lower')
  >     plt.xlabel('x [pixels]')
  >     plt.ylabel('y [pixels]')
  >     plt.colorbar()
  >     plt.show()

  > (Source code, png, hires.png, pdf)