set

来源： https://stackoverflow.com/questions/36548938/advantages-of-set-in-ruby

来源： https://stackoverflow.com/questions/15751019/what-is-the-fastest-way-to-check-if-a-string-contains-repeating-characters-in-py

来源： https://stackoverflow.com/questions/31121349/ways-around-using-a-double-as-a-key-in-a-std-set-map

来源： https://stackoverflow.com/questions/35644138/weird-order-in-sets-in-clojure

来源： https://stackoverflow.com/questions/35644138/weird-order-in-sets-in-clojure

来源： https://stackoverflow.com/questions/13692700/good-way-to-get-any-value-from-a-java-set

来源： https://stackoverflow.com/questions/13692700/good-way-to-get-any-value-from-a-java-set

问题 This is my dataframe: pd.DataFrame({'A':[1, 3, 3, 4, 5, 3, 3], 'B':[0, 2, 3, 4, 5, 6, 7], 'C':[[1,4,4,4], [1,4,4,4], [3,4,4,5], [3,4,4,5], [4,4,2,1], [1,2,3,4,], [7,8,9,1]]}) I want to get set\drop duplicate values of column C per row but not drop duplicate rows. This what I hope to get: pd.DataFrame({'A':[1, 3, 3, 4, 5, 3, 3], 'B':[0, 2, 3, 4, 5, 6, 7], 'C':[[1,4], [1,4], [3,4,5], [3,4,5], [4,2,1], [1,2,3,4,], [7,8,9,1]]}) 回答1: If you're using python 3.7>, you could could map with dict

问题 I'm trying to add in Integer array into Set as following, int[] arr = { 2, 6, 4 , 2, 3, 3, 1, 7 }; Set<Integer> set = new HashSet<Integer>(Arrays.asList(arr)); I'm getting some error telling as following, myTest.java:192: error: no suitable constructor found for HashSet(List<int[]>) Set<Integer> set = new HashSet<Integer>(Arrays.asList(arr)); ^ constructor HashSet.HashSet(Collection<? extends Integer>) is not applicable (argument mismatch; inferred type does not conform to upper bound(s)

问题 I'm trying to add in Integer array into Set as following, int[] arr = { 2, 6, 4 , 2, 3, 3, 1, 7 }; Set<Integer> set = new HashSet<Integer>(Arrays.asList(arr)); I'm getting some error telling as following, myTest.java:192: error: no suitable constructor found for HashSet(List<int[]>) Set<Integer> set = new HashSet<Integer>(Arrays.asList(arr)); ^ constructor HashSet.HashSet(Collection<? extends Integer>) is not applicable (argument mismatch; inferred type does not conform to upper bound(s)