ordereddictionary

问题 I have a file with no extension with lines like this (ignore the spacing between the lines, but each line is a separate row): OrderedDict([('key1', u'value1'), ('key2', 'value2')]) OrderedDict([('key1', u'value1'), ('key2', 'value2')]) OrderedDict([('key1', u'value1'), ('key2', 'value2')]) when I import it to Python snap_fh = open("C:\Users\.......") for row in snap_fh: print(type(row)) rows are "strings" and I cannot parse it as an OrderedDictionary "OrderedDict([('key1', u'value1'), ('key2'

问题 I'm using an OrderedDict to random access a list, but now want the next item in the list from the one that I have: foo = OrderedDict([('apple', 4), ('banana', 3), ('orange', 2), ('pear', 1)]) apple = foo['apple'] How do I get the banana using just foo and apple ? 回答1: If you are OK with accessing those parts of the OrderedDict implementation that are intentionally kept private: >>> class MyOrderedDict(OrderedDict): ... def next_key(self, key): ... next = self._OrderedDict__map[key][1] ... if

问题 I'm trying to query information from salesforce using the simple_salesforce package in python. The problem is that it's nesting fields that are a part of a parent-child relationship into an ordered dict within an ordered dict I want.. from the Opportunity object, to find the id, and the accountid associated with that record. The SOQL query may look like.. query = "select id, account.id from opportunity where closedate = last_n_days:5" in SOQL (salesforce object query language), a dot denotes

问题 I'm trying to query information from salesforce using the simple_salesforce package in python. The problem is that it's nesting fields that are a part of a parent-child relationship into an ordered dict within an ordered dict I want.. from the Opportunity object, to find the id, and the accountid associated with that record. The SOQL query may look like.. query = "select id, account.id from opportunity where closedate = last_n_days:5" in SOQL (salesforce object query language), a dot denotes

问题 Deleting a key from a python dict or defaultdict in python is O(1) operation, as mentioned here and here. To remove a key from OrderedDict , we can either use del d[key] or use popitem() method, as mentioned in the docs. What is the underlying implementation of OrderedDict and the time complexity of del operation? Edit: This answer OrderedDict performance (compared to deque) , refers to the complexity of del in OrderedDict as being O(1). However, how can we justify it at implementation detail

问题 I have an ordered dictionary ( OrderedDict ) sorted by value. How can I get the top (say 25) key values and add them to a new dictionary? For example: I have something like this: dictionary={'a':10,'b':20,'c':30,'d':5} ordered=OrderedDict(sorted(dictionary.items(), key=lambda x: x[1],reverse=True)) Now ordered is an ordered dictionary, I want to create a dictionary, say by taking the top 2 most-frequent items and their keys: frequent={'c':30,'b':20} 回答1: The primary purpose of collections

问题 I have a parent class, and I want to keep a registry (in the form of a dictionary) of all instances of its sub-classes. Easy, but I want the registry to sort itself based on its keys, which are the arguments of the 2 sub-classes on initialisation. This is my code in simplified form: from collections import OrderedDict class Parent: _registry = OrderedDict() def __init__(self): # add each sub-class instance to the registry & sort the registry self._registry.update({self._num:self}) self.

问题 I have the following OrderedDict : from collections import OrderedDict a = OrderedDict() a['2016:April'] = 1 a['2016:January'] = 2 a['2017:February'] = 3 a['2015:November'] = 4 I would like to sort the dictionary by the keys in chronological order so that the result is: OrderedDict([('2015:November', 4), ('2016:January', 2), ('2016:April', 1), ('2017:February', 3)]) 回答1: You need to recreate the OrderedDict by passing sorted items; (OrderedDict remembers key insertion order) import calendar

问题 My hashtable contains (key, Values[]) e.g: myHashtable[keys, Values[]] myHashtable.Add[1, Value1]; myHashtable.Add[2, Value2]; myHashtable.Add[3, Value3]; myHashtable.Add[4, Value4]; myHashtable.Add[5, Value5]; Where Value1; Value2, value3, value4, and value5 is as follows. Value1[name = "Smith"] Value1[Title= "Mr"] Value1[Salary = 1000] Value1[Identity = "S"] Value2[name = "Peter"] Value2[Title= "Mr"] Value2[Salary = 1000] Value2[Identity = "A"] Value3[name = "Tom"] Value3[Title= "Mr"]

问题 My hashtable contains (key, Values[]) e.g: myHashtable[keys, Values[]] myHashtable.Add[1, Value1]; myHashtable.Add[2, Value2]; myHashtable.Add[3, Value3]; myHashtable.Add[4, Value4]; myHashtable.Add[5, Value5]; Where Value1; Value2, value3, value4, and value5 is as follows. Value1[name = "Smith"] Value1[Title= "Mr"] Value1[Salary = 1000] Value1[Identity = "S"] Value2[name = "Peter"] Value2[Title= "Mr"] Value2[Salary = 1000] Value2[Identity = "A"] Value3[name = "Tom"] Value3[Title= "Mr"]