sorting

问题 As input I have 2D array PointXY[ ][ ] clusters, which looks like this: [[23.237633,53.78671], [69.15293,17.138134], [23.558687,45.70517]] . . . [[47.851738,16.525734], [47.802097,16.689285], [47.946404,16.732542]] [[47.89601,16.638218], [47.833263,16.478987], [47.88203,16.45793]] [[47.75438,16.549816], [47.915512,16.506475], [47.768547,16.67624]] . . . So elements in array are of type PointXY[ ], defined like this public PointXY(float x, float y) { this.x = x; this.y = y; } what I would like

问题 i'm making a sorting algorithm on CUDA for a bigger project and i decided implementing a Bitonic sorting. The number of elements i'll be sorting will be allways a power of two, in fact will be 512. I need an array which will have the final positions because this method will be used for ordering an array that represents the quality matrix of another solution. fitness is the array i'll sort, numElements is the number of elements, and orden is initially an empty array with numElements positions

问题 okay so I know how I can sort by id or number like $getTicket = $sql->query("SELECT * FROM `ticket` WHERE `user`='$user->name' ORDER BY `id` DESC"); I have Status in the ticket table, and in that I have 3 things: 1) Answered 2) Unanswered 3) Done I want to sort it in this way: 1) Unanswered 2) Answered 3) Done is there a way to do this? 回答1: Do simple as- ORDER BY FIELD(Status, 'Unanswered', 'Answered', 'Done') 回答2: You can generally use case SELECT * FROM `ticket` WHERE `user` = '$user->name

问题 I have a structured numpy array: dtype = [('price', float), ('counter', int)] values = [(35, 1), (36, 2), (36, 3)] a = np.array(values, dtype=dtype) I want to sort for price and then for counter if price is equal: a_sorted = np.sort(a, order=['price', 'counter'])[::-1] I need the price in a descending order and when prices are equal consider counter in ASCENDING order. In the example above both the price and the counter are in descending order. What I get is: a_sorted: [(36., 3), (36., 2),

问题 At the risk of being a bit off-topic, I want to show a simple solution for loading large csv files in a dask dataframe where the option sorted=True can be applied and save a significant time of processing. I found the option of doing set_index within dask unworkable for the size of the toy cluster I am using for learning and the size of the files (33GB). So if your problem is loading large unsorted CSV files, ( multiple tens of gigabytes ), into a dask dataframe and quickly start performing

问题 I'm working with an image retrieval system using color histogram intersection in MATLAB. This method gives me the following data: a real number which represents the histogram intersection distance, and the image file name. Because they are different data types, I store them in structure array with two fields, and then I save this structure in a .mat file. Now I need to sort this structure according to the histogram intersection distance in descending order in order to retrieve the image with

问题 In other words, find the lowest positive integer that does not exist in the array. The array can contain duplicates and negative numbers as well. This question was asked by Stripe in it's programming interview. I have devised a solution for the same as below: #include<bits/stdc++.h> using namespace std; int main(){ int arr[]={1,-1,-5,-3,3,4,2,8}; int size= sizeof(arr)/sizeof(arr[0]); sort(arr, arr+size); int min=1; for(int i=0; i<size; i++){ if(arr[i]>min) break; if(arr[i]==min) min=min+1; }

问题 I have the file which stores the data in the below format TIME[04.26_12:30:30:853664]ID[ROLL:201987623]MARKS[PHY:100|MATH:200|CHEM:400] TIME[03.27_12:29:30.553669]ID[ROLL:201987623]MARKS[PHY:100|MATH:1200|CHEM:900] TIME[03.26_12:28:30.753664]ID[ROLL:2341987623]MARKS[PHY:100|MATH:200|CHEM:400] TIME[03.26_12:29:30.853664]ID[ROLL:201978623]MARKS[PHY:0|MATH:0|CHEM:40] TIME[04.27_12:29:30.553664]ID[ROLL:2034287623]MARKS[PHY:100|MATH:200|CHEM:400] Below method I found to fulfill the need given in

问题 To sort I call qsort(myArray,100,sizeof(int), comp) int comp(const int * a, const int * b) if(a==b) { return 0; } else { if(a<b) { return -1; } else { return 1; } } First, This doesn't really work, when I sort an array (9,8,7,6,5,4,3,2,1,1), I get (4,8,7,6,5,9,3,2,1) - NOT really sorted. Second, How would I sort in the other direction? Is there a special flag for qsort I need to pass? 回答1: Change your compare function so that it is ordering the way you like. And the compare function takes

问题 Let say I have a file as below: number 2 6 7 10 number 6 13 name1 A B C D name1 B E name2 A B C D name2 B E name3 B A D A name3 A F name4 B A D A name4 A F I wish to remove the entirely the same duplicate columns and the output file is as below: number 2 6 7 10 13 name1 A B C D E name2 A B C D E name3 B A D A F name4 B A D A F I use sort and uniq command for lines but never know how to do for columns. Can anyone suggest a good way? 回答1: Here is a way with awk that preserves the order awk 'NR=