sorting

问题 I have an array like this var temp = [{"rank":3,"name":"Xan"},{"rank":1,"name":"Man"},{"rank":2,"name":"Han"}] I am trying to sort it as follows temp.sort(function(a){ a.rank}) But its n ot working.Can anyone suggest help.Thanks. 回答1: With Array#sort, you need to check the second item as well, for a symetrical value and return a value. var temp = [{ rank: 3, name: "Xan" }, { rank: 1, name: "Man" }, { rank: 2, name: "Han" }]; temp.sort(function(a, b) { return a.rank - b.rank; }); console.log

问题 I'd like to order a data.table by a variable holding the name of a column: I've tried every combination of + eval , get and c` without success: I have colVar = "someColumnName" I'd like to apply this to: DT[order(colVar)] 回答1: You can use double brackets for data tables: library(data.table) dtbl <- data.table(x = 1:5, y = 5:1) colVar = "y" dtbl_sorted <- dtbl[order(dtbl[[colVar]])] dtbl_sorted 回答2: data.table has special functions for that matter which will modify your data set by reference

问题 Hello Trying to sort this list by Month and day. Can not get it staight. Any pointers ? List example: Jul 23 Drive :NTFS (Windows 31.6 GB/29.4 GiB) Details : Mounted /dev/sdc1 (Read-Write, label "FreeAgent GoFlex Drive", NTFS 3.1) Jul 30 Drive :NTFS (Windows 31.6 GB/29.4 GiB) Details : Mounted /dev/sdb1 (Read-Write, label "HP USB FD", NTFS 3.1) Aug 2 Drive :NTFS (Windows 31.6 GB/29.4 GiB) Details : Mounted /dev/sdb1 (Read-Write, label "WINPART", NTFS 3.1) Jul 24 Drive :EXT (Linux) Details :

问题 Hello Trying to sort this list by Month and day. Can not get it staight. Any pointers ? List example: Jul 23 Drive :NTFS (Windows 31.6 GB/29.4 GiB) Details : Mounted /dev/sdc1 (Read-Write, label "FreeAgent GoFlex Drive", NTFS 3.1) Jul 30 Drive :NTFS (Windows 31.6 GB/29.4 GiB) Details : Mounted /dev/sdb1 (Read-Write, label "HP USB FD", NTFS 3.1) Aug 2 Drive :NTFS (Windows 31.6 GB/29.4 GiB) Details : Mounted /dev/sdb1 (Read-Write, label "WINPART", NTFS 3.1) Jul 24 Drive :EXT (Linux) Details :

问题 How do I sort an array in Rails (alphabetical order). I have tried: sort_by(&:field_name) which that gives me an array with capital letter order and then lower case order. I have tried: array.sort! { |x,y| x.field_name.downcase <=> y.field_name.downcase } Is there any way to solve this? 回答1: You should first downcase every string and then sort like: array = ["john", "Alice", "Joseph", "anna", "Zilhan"] array.sort_by!{ |e| e.downcase } => ["Alice", "anna", "john", "Joseph", "Zilhan"] 回答2: Be

问题 I have made a bubble sort algorithm (sorta) using JS. It works sometimes, but the problem is that it only iterates through the array once. Here is my code: function bubble(arr) { for (var i = 0; i < arr.length; i++) { if (arr[i] > arr[i + 1]) { var a = arr[i] var b = arr[i + 1] arr[i] = b arr[i + 1] = a } } return arr; } 回答1: You need an inner loop to complete the sort correctly: function bubble(arr) { var len = arr.length; for (var i = 0; i < len ; i++) { for(var j = 0 ; j < len - i - 1; j++

问题 I have made a bubble sort algorithm (sorta) using JS. It works sometimes, but the problem is that it only iterates through the array once. Here is my code: function bubble(arr) { for (var i = 0; i < arr.length; i++) { if (arr[i] > arr[i + 1]) { var a = arr[i] var b = arr[i + 1] arr[i] = b arr[i + 1] = a } } return arr; } 回答1: You need an inner loop to complete the sort correctly: function bubble(arr) { var len = arr.length; for (var i = 0; i < len ; i++) { for(var j = 0 ; j < len - i - 1; j++

问题 My question is similar to the one asked here: http://forum.springsource.org/showthread.php?84508-jdbctemplate.query()-sorted-result-set but a clear answer was not provided - an ArrayList does not guarantee order. Basically, I would like to know if the call returned by jdbcTemplate.query() guarantees the order of the resultset and if I can dump it into a LinkedList and pass it along :) Thanks! Edit: I should clarify that the query does include an order by clause, hence my requirements for a

问题 I have a list of lines read from a file. I need to sort the list by time stamp. I have parsed out the time stamp using regular expressions and place them into a separate list. The indices of the two lists will match. Once I sort the list of time stamps, I can get the order of indices. Is there a way to apply the same order of indices to the original list of lines? The result should be the sorted list of original lines. Example: listofLines = ['log opened 16-Feb-2010 06:37:56 UTC', '06:37:58

问题 I haven't found something in my research so I thought someone can help me here. My problem is that I want to sort an array of objects which contains a status: { "data":[ { "status":"NEW" }, { "status":"PREP" }, { "status":"CLOS" }, { "status":"END" }, { "status":"ERR" }, { "status":"PAUS" } ] } Now I want to set a fixed sort order like all objects with the status "END" coming first then all objects with the status "PREP" and so on. Is there a way to do that in JavaScript? Thanks in advance :)