np.where(nums == 0): Use the np.where() function to find the indices of elements in the 'nums' array that are equal to 0. The expression nums == 0 creates a boolean array of the same shape as 'nums', with True a
numpy.unique(ar, return_index=False, return_inverse=False, return_counts=False, axis=None)Find the unique elements of an array. return_index=True 表示返回新列表元素在旧列表中的位置。 return_inverse=True表示返回旧列表元素在新列表中的位置。 return_counts=True表示返回新列表元素在旧列表中出现的次数...
checking whether each element in a is greater than or equal to 7 and less than or equal to 20. The result is a boolean array where each element is True if both conditions are met and False otherwise.
numpy.in1d(ar1, ar2, assume_unique=False, invert=False)Test whether each element of a 1-D array is also present in a second array. Returns a boolean array the same length asar1that is True where an element ofar1is inar2and False otherwise. 【例】前面的数组是否包含于后面的数组,返回...
math:: Q'(s, a) \leftarrow \text{avg}(\text{reward following first visit to } (s, a) \text{ across all episodes}) RL agents seek to learn action values conditional on subsequent optimal behavior, but they need to behave non-optimally in order to explore all actions (to find the ...
# Find inverse of a given matrix >>> np.linalg.inv([[3,1],[2,4]]) array([[ 0.4, -0.1], [-0.2, 0.3]]) 数学计算 操作 操作 描述 文档 np.add(x,y)x + y 加 https://docs.scipy.org/doc/numpy/reference/generated/numpy.add.html np.substract(x,y)x - y 减 https://docs.sci...
Return a with each element rounded to the given number of decimals. searchsorted(v[, side, sorter]) Find indices where elements of v should be inserted in a to maintain order. setfield(val, dtype[, offset]) Put a value into a specified place in a field defined by a data-type. set...
[1,2,0,0,4,0])# Find indices of non-zero elementsprint(nz)# (array([0, 1, 4], dtype=int64),)"""上面是前十道题中不会的"""# identity matrix单位矩阵print(np.eye(3))# 3*3的单位矩阵# [[1. 0. 0.]# [0. 1. 0.]# [0. 0. 1.]]# Create a 2d array with 1 on the...
8. Reverse a vector (first element becomes last) >>Z = np.arange(50) Z = Z[::-1] print(Z) 9. Create a 3x3 matrix with values ranging from 0 to 8? >>Z = np.arange(9) Z = Z.reshape(3,3) print(Z) 10. Find indices of non-zero elements from [1,2,0,0,4,0] ?
bool_idx = (a >2)# Find the elements of a that are bigger than 2;# this returns a numpy array of Booleans of the same# shape as a, where each slot of bool_idx tells# whether that element of a is > 2.print(bool_idx)# Prints "[[False False]# [ True True]# [ True True]...