79 lines
		
	
	
	
		
			2.5 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
		
		
			
		
	
	
			79 lines
		
	
	
	
		
			2.5 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
|   | from __future__ import annotations | ||
|  | 
 | ||
|  | from typing import TYPE_CHECKING, Any | ||
|  | 
 | ||
|  | import numpy as np | ||
|  | 
 | ||
|  | if TYPE_CHECKING: | ||
|  |     from contourpy._contourpy import CoordinateArray | ||
|  | 
 | ||
|  | 
 | ||
|  | def simple( | ||
|  |     shape: tuple[int, int], want_mask: bool = False, | ||
|  | ) -> tuple[CoordinateArray, CoordinateArray, CoordinateArray | np.ma.MaskedArray[Any, Any]]: | ||
|  |     """Return simple test data consisting of the sum of two gaussians.
 | ||
|  | 
 | ||
|  |     Args: | ||
|  |         shape (tuple(int, int)): 2D shape of data to return. | ||
|  |         want_mask (bool, optional): Whether test data should be masked or not, default ``False``. | ||
|  | 
 | ||
|  |     Return: | ||
|  |         Tuple of 3 arrays: ``x``, ``y``, ``z`` test data, ``z`` will be masked if | ||
|  |         ``want_mask=True``. | ||
|  |     """
 | ||
|  |     ny, nx = shape | ||
|  |     x = np.arange(nx, dtype=np.float64) | ||
|  |     y = np.arange(ny, dtype=np.float64) | ||
|  |     x, y = np.meshgrid(x, y) | ||
|  | 
 | ||
|  |     xscale = nx - 1.0 | ||
|  |     yscale = ny - 1.0 | ||
|  | 
 | ||
|  |     # z is sum of 2D gaussians. | ||
|  |     amp = np.asarray([1.0, -1.0, 0.8, -0.9, 0.7]) | ||
|  |     mid = np.asarray([[0.4, 0.2], [0.3, 0.8], [0.9, 0.75], [0.7, 0.3], [0.05, 0.7]]) | ||
|  |     width = np.asarray([0.4, 0.2, 0.2, 0.2, 0.1]) | ||
|  | 
 | ||
|  |     z = np.zeros_like(x) | ||
|  |     for i in range(len(amp)): | ||
|  |         z += amp[i]*np.exp(-((x/xscale - mid[i, 0])**2 + (y/yscale - mid[i, 1])**2) / width[i]**2) | ||
|  | 
 | ||
|  |     if want_mask: | ||
|  |         mask = np.logical_or( | ||
|  |             ((x/xscale - 1.0)**2 / 0.2 + (y/yscale - 0.0)**2 / 0.1) < 1.0, | ||
|  |             ((x/xscale - 0.2)**2 / 0.02 + (y/yscale - 0.45)**2 / 0.08) < 1.0, | ||
|  |         ) | ||
|  |         z = np.ma.array(z, mask=mask)  # type: ignore[no-untyped-call] | ||
|  | 
 | ||
|  |     return x, y, z | ||
|  | 
 | ||
|  | 
 | ||
|  | def random( | ||
|  |     shape: tuple[int, int], seed: int = 2187, mask_fraction: float = 0.0, | ||
|  | ) -> tuple[CoordinateArray, CoordinateArray, CoordinateArray | np.ma.MaskedArray[Any, Any]]: | ||
|  |     """Return random test data in the range 0 to 1.
 | ||
|  | 
 | ||
|  |     Args: | ||
|  |         shape (tuple(int, int)): 2D shape of data to return. | ||
|  |         seed (int, optional): Seed for random number generator, default 2187. | ||
|  |         mask_fraction (float, optional): Fraction of elements to mask, default 0. | ||
|  | 
 | ||
|  |     Return: | ||
|  |         Tuple of 3 arrays: ``x``, ``y``, ``z`` test data, ``z`` will be masked if | ||
|  |         ``mask_fraction`` is greater than zero. | ||
|  |     """
 | ||
|  |     ny, nx = shape | ||
|  |     x = np.arange(nx, dtype=np.float64) | ||
|  |     y = np.arange(ny, dtype=np.float64) | ||
|  |     x, y = np.meshgrid(x, y) | ||
|  | 
 | ||
|  |     rng = np.random.default_rng(seed) | ||
|  |     z = rng.uniform(size=shape) | ||
|  | 
 | ||
|  |     if mask_fraction > 0.0: | ||
|  |         mask_fraction = min(mask_fraction, 0.99) | ||
|  |         mask = rng.uniform(size=shape) < mask_fraction | ||
|  |         z = np.ma.array(z, mask=mask)  # type: ignore[no-untyped-call] | ||
|  | 
 | ||
|  |     return x, y, z |