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Method to Add new or update existing item in Dictionary
...] = value. The two options are equivalent.
Regarding Dictionary<> vs. Hashtable: When you start Reflector, you see that the indexer setters of both classes call this.Insert(key, value, add: false); and the add parameter is responsible for throwing an exception, when inserting a duplicate ke...
How to redirect a url in NGINX
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Just a quick warning: Watch out for the 301 redirect vs the 302. You could be stuck with a cached permanent redirect, which makes it very troublesome to change your settings for clients that have already accessed a URL. (I know the OP asked for a 301, but be sure that's reall...
Why dict.get(key) instead of dict[key]?
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One more good test would be if k in dict and dict[k]: vs if dict.get(k):. This covers the situation when we need to check if key exists, and if 'yes' - what value?, something like: dict = {1: '', 2: 'some value'}.
– TitanFighter
Sep 16 '17 ...
Find size of object instance in bytes in c#
...ze of an object, not the memory consumption of a runtime graph of objects. VS2017's memory and CPU profiling are very good, as are ReSharper's and other tools, and that's what I'd use to measure.
– jnm2
Mar 9 '17 at 18:23
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ASP.NET MVC 404 Error Handling [duplicate]
...reas. For more information see msdn.microsoft.com/en-us/library/ee671793(v=vs.100).aspx
– Marco
Jan 21 '14 at 16:58
3
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Regex to remove all (non numeric OR period)
... numbers and periods should stay - everything else filtered. I use C# and VS.net 2008 framework 3.5
5 Answers
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Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
...1038 0.121675 0.443863
You can assign it back to df to actually delete vs filter ing done above
df = df[(df > 0).all(axis=1)]
This can easily be extended to filter out rows containing NaN s (non numeric entries):-
df = df[(~df.isnull()).all(axis=1)]
This can also be simplified for cases li...
What are all possible pos tags of NLTK?
... either et for less minus neither nor or plus so
therefore times v. versus vs. whether yet
CD: numeral, cardinal
mid-1890 nine-thirty forty-two one-tenth ten million 0.5 one forty-
seven 1987 twenty '79 zero two 78-degrees eighty-four IX '60s .025
fifteen 271,124 dozen quintillion DM2,000 ...
D...
Select N random elements from a List in C#
... screw up the sort. The [documentation] (msdn.microsoft.com/en-us/library/vstudio/…) doesn't say which it does.
– Oliver Bock
Mar 5 '15 at 4:38
2
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PHP - Modify current object in foreach loop
...($value) ? $value*2 : $value; }, $arr);
var_dump($arr);
var_dump($arr2);
vs
<?php
$arr = [0,1,2,3,4];
foreach($arr as $i => $item) {
$arr[$i] = is_int($item) ? $item * 2 : $item;
}
var_dump($arr);
If you know what you are doing will never have mutability problems (bearing in mind if ...