如果您有哈希哈希如何删除First Hash的值 - Ruby
-
21-12-2019 - |
题
来自以下的最简单方法是什么:
{"Wednesday"=>{"Horse"=>{"9.0"=>1, "10.0"=>1}},
"Thursday"=>{"Horse"=>{"9.0"=>1, "10.0"=>1}}}
.
?
{"Wednesday"=>{"9.0"=>1, "10.0"=>1},
"Thursday"=>{"9.0"=>1, "10.0"=>1}}
.
我已经在我的控制台中挣扎了2个小时。
将欣赏任何答案!
p.s。这匹马是一种变化,如:法国人,Belgiansalion,Lipicanec ...
解决方案
a functional 样式解决方案(无需修改原始哈希或使用额外变量 - 为我看起来优雅的解决方案)
hash.reduce({}) { |acc, (k, v)| acc.merge(Hash[k, *v.values]) }
# => {"Wednesday"=>{"9.0"=>1, "10.0"=>1}, "Thursday"=>{"9.0"=>1, "10.0"=>1}}
. 其他提示
怎么样。
hash = {"Wednesday"=>{"Horse"=>{"9.0"=>1, "10.0"=>1}},
"Thursday"=>{"Horse"=>{"9.0"=>1, "10.0"=>1}}}
a ={}
hash.each do |k,v|
a[k]=v.values.first
end
. 这样做
a = {"Wednesday"=>{"Horse"=>{"9.0"=>1, "10.0"=>1}},
"Thursday"=>{"Horse"=>{"9.0"=>1, "10.0"=>1}}}
d = {}
a.each { |k,v| d[k] = v["Horse"] }
puts d
. Hash[]
方法派上友好地构建哈希:
hash = {
"Wednesday"=>{"Horse"=>{"9.0"=>1, "10.0"=>1}},
"Thursday"=>{"Horse"=>{"9.0"=>1, "10.0"=>1}}
}
x = "Horse"
Hash[
hash.collect do |k, v|
[ k, v[x] ]
end
]
# => {"Wednesday"=>{"9.0"=>1, "10.0"=>1}, "Thursday"=>{"9.0"=>1, "10.0"=>1}}
. 我会做
hash = {"Wednesday"=>{"Horse"=>{"9.0"=>1, "10.0"=>1}},
"Thursday"=>{"Horse"=>{"9.0"=>1, "10.0"=>1}}}
hash.each_with_object({}) { |(k,v),h| h[k] = v['Horse']}
# => {"Wednesday"=>{"9.0"=>1, "10.0"=>1}, "Thursday"=>{"9.0"=>1, "10.0"=>1}}
.
更新
hash.each_with_object({}) { |(k,v),h| h[k] = v.shift.last}
# => {"Wednesday"=>{"9.0"=>1, "10.0"=>1}, "Thursday"=>{"9.0"=>1, "10.0"=>1}}
. 一种方式是使用哈希#merge 采用块来确定两个哈希中存在的键的值:
h = { "Wednesday"=>{ "Horse"=>{ "9.0"=>1, "10.0"=>1 } },
"Thursday" =>{ "Horse"=>{ "9.0"=>1, "10.0"=>1 } } }
key = "Horse"
h.merge(h) { |*_,g| g[key] }
#=> { "Wednesday"=>{ "9.0"=>1, "10.0"=>1 },
# "Thursday" =>{ "9.0"=>1, "10.0"=>1 } }
. 不隶属于 StackOverflow