在多个轴上对二维数组进行排序

Question

我有以下数组：

tasks = [["LNWBN","2017-08-13","2017-12-24","Corey","Kyle","Kaleb","Reuben"], 

["NSXEN","2017-08-20","2017-09-18","Kai"], 

["DNMDC","2017-06-19","2017-08-07","Kaleb","Kai","Kyle","Reuben"], 

["UYWEQ","2017-04-23","2017-07-18","Corey","Kyle","Reuben","Kai"], 

["LIVNH","2017-11-01","2017-12-24","Kaleb","Kai"]]

我想按第三列排序，然后按第一列排序，结果是：

tasks = [["UYWEQ","2017-04-23","2017-07-18","Corey","Kyle","Reuben","Kai"], 

["DNMDC","2017-06-19","2017-08-07","Kaleb","Kai","Kyle","Reuben"], 

["NSXEN","2017-08-20","2017-09-18","Kai"], 

["LIVNH","2017-11-01","2017-12-24","Kaleb","Kai"],

["LNWBN","2017-08-13","2017-12-24","Corey","Kyle","Kaleb","Reuben"]]  

我尝试使用 lexsort：

a = np.array(tasks)

ind = np.lexsort((a[:,2],a[:,0]))    

sorted_tasks = a[ind]

这是这里的最佳解决方案Sorting a 2D numpy array by multiple axis 但出现以下错误：

  ind = np.lexsort((a[:,2],a[:,0]))

IndexError: too many indices for array: array is 1-dimensional, but 2 were indexed

我不必使用 numpy，但这是我发现按多个轴对 2D 数组进行排序的唯一方法

Answer 1

你为什么不试试 python 的sorted：sorted(tasks, key=lambda x: (x[2],x[0]))输出：[['UYWEQ', '2017-04-23', '2017-07-18', 'Corey', 'Kyle', 'Reuben', 'Kai'], ['DNMDC', '2017-06-19', '2017-08-07', 'Kaleb', 'Kai', 'Kyle', 'Reuben'], ['NSXEN', '2017-08-20', '2017-09-18', 'Kai'], ['LIVNH', '2017-11-01', '2017-12-24', 'Kaleb', 'Kai'], ['LNWBN', '2017-08-13', '2017-12-24', 'Corey', 'Kyle', 'Kaleb', 'Reuben']]