histogram2d

sherpa.utils.histogram2d(x, y, x_grid, y_grid)[source] [edit on github]

Create 2D histogram from a sequence of samples.

See the numpy.histogram2d routine for a version with more options.

Parameters
  • x (sequence of numbers) – The array of samples (X coordinate)

  • y (sequence of numbers) – The array of samples (Y coordinate), which must have the same size as the x sequence.

  • x_grid (sequence of numbers) – The X bin edges.

  • y_grid (sequence of numbers) – The Y bin edges.

Returns

y – The number of samples in each histogram bin defined by the x_grid and y_grid arrays.

Return type

NumPy array

Examples

Given a list of coordinates (xvals, yvals), bin them up so that they match the 5 by 10 pixel image data space. In this case the X grid is [1, 2, …, 5] and the Y grid is [1, 2, .., 10].

>>> dataspace2d([5, 10])
>>> (xgrid, ygrid) = get_axes()
>>> n = histogram2d(xvals, yvals, xgrid, ygrid)
>>> set_dep(n)