Slowest and doesn’t work in Python3: concatenate the items and call dict on the resulting list: $ python -mtimeit -s’d1={1:2,3:4}; d2={5:6,7:9}; d3={10:8,13:22}’ \ ‘d4 = dict(d1.items() + d2.items() + d3.items())’ 100000 loops, best of 3: 4.93 usec per loop Fastest: exploit the dict constructor to the hilt, then one update: $ python -mtimeit -s’d1={1:2,3:4}; d2={5:6,7:9}; … Read more
As you’d expect: sum(d.values())
dict.fromkeys directly solves the problem: >>> dict.fromkeys([1, 2, 3, 4]) {1: None, 2: None, 3: None, 4: None} This is actually a classmethod, so it works for dict-subclasses (like collections.defaultdict) as well. The optional second argument, which defaults to None, specifies the value to use for the keys. Note that the same object will be … Read more
A list keeps order, dict and set don’t: when you care about order, therefore, you must use list (if your choice of containers is limited to these three, of course 😉 ). dict associates each key with a value, while list and set just contain values: very different use cases, obviously. set requires items to … Read more
There’s no way to specify a StringComparer at the point where you try to get a value. If you think about it, “foo”.GetHashCode() and “FOO”.GetHashCode() are totally different so there’s no reasonable way you could implement a case-insensitive get on a case-sensitive hash map. You can, however, create a case-insensitive dictionary in the first place … Read more
You can access the namespace’s dictionary with vars(): >>> import argparse >>> args = argparse.Namespace() >>> args.foo = 1 >>> args.bar = [1,2,3] >>> d = vars(args) >>> d {‘foo’: 1, ‘bar’: [1, 2, 3]} You can modify the dictionary directly if you wish: >>> d[‘baz’] = ‘store me’ >>> args.baz ‘store me’ Yes, it … Read more
You could use if type(ele) is dict or use isinstance(ele, dict) which would work if you had subclassed dict: d = {‘abc’: ‘abc’, ‘def’: {‘ghi’: ‘ghi’, ‘jkl’: ‘jkl’}} for element in d.values(): if isinstance(element, dict): for k, v in element.items(): print(k,’ ‘,v)
The to_dict() method sets the column names as dictionary keys so you’ll need to reshape your DataFrame slightly. Setting the ‘ID’ column as the index and then transposing the DataFrame is one way to achieve this. to_dict() also accepts an ‘orient’ argument which you’ll need in order to output a list of values for each … Read more
Edit: This has since been fixed in the latest TS versions. Quoting @Simon_Weaver’s comment on the OP’s post: Note: this has since been fixed (not sure which exact TS version). I get these errors in VS, as you would expect: Index signatures are incompatible. Type ‘{ firstName: string; }’ is not assignable to type ‘IPerson’. … Read more
There’s public static class AbstractMap.SimpleEntry<K,V>. Don’t let the Abstract part of the name mislead you: it is in fact NOT an abstract class (but its top-level AbstractMap is). The fact that it’s a static nested class means that you DON’T need an enclosing AbstractMap instance to instantiate it, so something like this compiles fine: Map.Entry<String,Integer> … Read more