如何将新的键值对添加到现有字典中?

时间:2020-01-11 22:41:56

标签: julia

我有一些已经存在的字典。我想添加一个新的键值对,但是我不想从头开始创建一个新的字典。

如何在Julia中现有的词典中添加新的键值对?

1 个答案:

答案 0 :(得分:5)

Julia使用常见的dict[key] = value语法来设置键值对:

julia> dict = Dict(1 => "one")
Dict{Int64,String} with 1 entry:
  1 => "one"

julia> dict[2] = "two"
"two"

julia> dict
Dict{Int64,String} with 2 entries:
  2 => "two"
  1 => "one"

如果键已经存在,则相同的语法将覆盖键值对:

julia> dict
Dict{Int64,String} with 2 entries:
  2 => "two"
  1 => "one"

julia> dict[1] = "foo"
"foo"

julia> dict
Dict{Int64,String} with 2 entries:
  2 => "two"
  1 => "foo"

dict[key] = valuesetindex!调用的语法。尽管不常见,但是您可以直接致电setindex!

julia> dict = Dict(1 => "one")
Dict{Int64,String} with 1 entry:
  1 => "one"

julia> setindex!(dict, "two", 2)
Dict{Int64,String} with 2 entries:
  2 => "two"
  1 => "one"