mirror of https://github.com/pyodide/pyodide.git
28 lines
861 B
Python
28 lines
861 B
Python
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#from: https://github.com/iskandr/parakeet/blob/master/benchmarks/nd_local_maxima.py
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#setup: import numpy as np ; shape = (3,4,3,2) ; x = np.arange(72, dtype=np.float64).reshape(*shape)
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#run: local_maxima(x)
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#pythran export local_maxima(float [][][][])
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import numpy as np
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def wrap(pos, offset, bound):
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return ( pos + offset ) % bound
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def clamp(pos, offset, bound):
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return min(bound-1,max(0,pos+offset))
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def reflect(pos, offset, bound):
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idx = pos+offset
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return min(2*(bound-1)-idx,max(idx,-idx))
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def local_maxima(data, mode=wrap):
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wsize = data.shape
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result = np.ones(data.shape, bool)
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for pos in np.ndindex(data.shape):
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myval = data[pos]
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for offset in np.ndindex(wsize):
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neighbor_idx = tuple(mode(p, o-w//2, w) for (p, o, w) in zip(pos, offset, wsize))
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result[pos] &= (data[neighbor_idx] <= myval)
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return result
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