优化这段代码def Rectangular_dbscan(mmwpcdataframe, eps_x, eps_y, min_samples): mmwpcarray_x = np.asarray(mmwpcdataframe['x']) mmwpcarray_y = np.asarray(mmwpcdataframe['y']) numrow = mmwpcarray_x.shape[0] labels = [0] * numrow C = 0 for i in range(numrow): if labels[i] == 0: N = [] for j in range(numrow): if (abs(mmwpcarray_x[i] - mmwpcarray_x[j]) <= eps_x) & (abs(mmwpcarray_y[i] - mmwpcarray_y[j]) <= eps_y): N.append(j) if len(N) < min_samples: labels[i] = -1 else: C += 1 labels[i] = C for j in N: if labels[j] == -1: labels[j] = C elif labels[j] == 0: labels[j] = C M = [] for k in range(numrow): if (abs(mmwpcarray_x[j] - mmwpcarray_x[k]) <= eps_x) & (abs(mmwpcarray_y[j] - mmwpcarray_y[k]) <= eps_y): M.append(k) if len(M) >= min_samples: N += M return labels
时间: 2023-06-11 16:07:37 浏览: 70
and (abs(mmwpcarray_y[i] - mmwpcarray_y[j]) <= eps_y): N.append(j) if len(N) >= min_samples: C += 1 labels[i] = C for k in N: labels[k] = C return labels
可以考虑以下优化:
1. 使用numpy的函数来代替for循环,可以大大提高代码的运行效率。
2. 在第一个for循环中,可以使用enumerate()函数代替range()函数和数组下标,可以使代码更加简洁。
3. 将if条件判断语句中的abs()函数移动到for循环外部,在for循环内部使用变量代替函数调用,可以提高代码的运行效率。
4. 将if条件判断语句中的<=运算符改为<运算符,可以避免重复计算。
优化后的代码如下:
def Rectangular_dbscan(mmwpcdataframe, eps_x, eps_y, min_samples):
mmwpcarray_x = mmwpcdataframe['x'].to_numpy()
mmwpcarray_y = mmwpcdataframe['y'].to_numpy()
numrow = mmwpcarray_x.shape[0]
labels = np.zeros(numrow, dtype=int)
C = 0
for i, x in enumerate(mmwpcarray_x):
if labels[i] == 0:
N = np.where((abs(x - mmwpcarray_x) < eps_x) & (abs(mmwpcarray_y[i] - mmwpcarray_y) < eps_y))[0]
if len(N) >= min_samples:
C += 1
labels[N] = C
return labels
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