迭代 Julia 中数组的每个索引 – eachindex() 方法

eachindex()是 julia 中的一个内置函数，用于创建一个可迭代对象，用于访问指定数组的每个索引。

Syntax:
eachindex(A…)

Parameters:

• A: Specified array.

Returns: It returns an iterable object for visiting each index of the specified array.

示例 1：

# Julia program to illustrate 
# the use of Array eachindex() method
  
# Accessing each index of 1D array 
A = [1, 2, 3, 4];
  
# linear indexing
for i in eachindex(A)
    println(i)
end
  
# Accessing each index of 2D array 
B = [2 4; 6 8];
  
# linear indexing
for i in eachindex(B)
    println(i)
end
  
# Accessing each index of 3D array 
C = cat([1 2; 3 4], [5 6; 7 8], [2 2; 3 4], dims = 3);
  
# linear indexing
for i in eachindex(C)
    println(i)
end

输出：
示例 2：

# Julia program to illustrate 
# the use of Array eachindex() method
  
# Accessing each index of 1D array 
A = [1, 2, 3, 4];
  
# Cartesian indexing
for i in eachindex(view(A, 1:2, 1:1)) 
    println(i)
end
  
# Accessing each index of 2D array 
B = [2 4; 6 8];
  
# Cartesian indexing
for i in eachindex(view(B, :, 1)) 
    println(i)
end
  
# Accessing each index of 3D array 
C = cat([1 2; 3 4], [5 6; 7 8], [2 2; 3 4], dims = 3);
  
# Cartesian indexing
for i in eachindex(view(C, :, :, 1)) 
    println(i)
end

输出：