importnumpyasnp arr=np.array([2,4,6,8,10])index=np.where(arr==6)print("Index of number 6:",index)index=np.argwhere(arr==6)print("Index of number 6:",index)index=np.where(arr==6)[0][0]print("Index of number 6:",
With two-dimensional arrays, the first index specifies the row of the array and the second index 对于二维数组,第一个索引指定数组的行,第二个索引指定行 specifies the column of the array. 指定数组的列。 This is exactly the way we would index elements of a matrix in linear algebra. 这正是我...
from numpy import array # define array data = array([11, 22, 33, 44, 55]) # index data print(data[0]) print(data[4]) 运行示例,该示例打印数组中的第一个值和最后一个值。 代码语言:txt AI代码解释 11 55 指定大于边界的值将导致错误。 代码语言:txt AI代码解释 # simple indexing from num...
4) >>> b = a > 4 >>> b # `b` is a boolean with `a`'s shape array([[False,...
Generally speaking, what is returned when index arrays are used is an array with the same shape as the index array, but with the type and values of the array being indexed. 以二维数组为例: >>>importnumpyasnp>>>x = np.arange(12).reshape(3,4)>>>x ...
index with slice slice还可以作为index使用,作为index使用表示的就是一个index范围值。 作为index表示的slice可以有多种形式。 有头有尾的,表示index从1开始到6-1结束: arr[1:6] array([ 1, 2, 3, 4, 64]) 无头有尾的,表示index从0开始,到尾-1结束: arr2d[:2] array([[1, 2, 3], [4, 5...
# Removeindex2frompreviousarray print(np.delete(b,2)) >>> [12456789] 组合数组 举例: importnumpyasnp a = np.array([1,3,5]) b = np.array([2,4,6]) # Stack two arrays row-wise print(np.vstack((a,b))) >>>[[135] [246]] ...
In NumPy, each element in an array is associated with a number.In NumPy, each element in an array is associated with a number. The number is known as an array index. Let's see an example to demonstrate NumPy array indexing. Array Indexing in NumPy In the
[1,2,3,4,5])>>> a[2]3>>> a[1:4:2]array([2, 4])>>> a[1:3]array([2, 3])>>> a[0::2]array([1, 3, 5])>>> a[5]Traceback (most recent call last):File "<pyshell#15>", line 1, in <module>a[5]IndexError: index 5 is out of bounds for axis 0 with size...
>>> s = np.array([i, j]) >>> # not what we want >>> a[s] Traceback (most recent call last): File "<stdin>", line 1, in <module> IndexError: index 3 is out of bounds for axis 0 with size 3 >>> # same as `a[i, j]` >>> a[tuple(s)] array([[ 2, 5], [...