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How to use LINQ to select object with minimum or maximum property value
...re consistent with methods like First() and the approach of the Dictionary indexer. You could easily adapt it if you wanted though.
– Jon Skeet
May 27 '09 at 6:40
8
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Why does range(start, end) not include end?
...s which equals len(range(0, 10)). Remember that programmers prefer 0-based indexing.
Also, consider the following common code snippet:
for i in range(len(li)):
pass
Could you see that if range() went up to exactly len(li) that this would be problematic? The programmer would need to explicitl...
How to Generate unique file names in C#
...upplied. If the original file exists, it incrementally tries to append an index to the filename until it finds one that doesn't exist. It reads the existing filenames into a HashSet to check for collisions so it's pretty quick (a few hundred filenames per second on my machine), it's thread safe to...
Finding last occurrence of substring in string, replacing that
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@AdamMagyar yes, container[a:b] slices from a up to b-1 index of the container. If 'a' is omitted, then it defaults to 0; if 'b' is omitted it defaults to len(container). The plus operator just concatenates. The rfind function as you pointed out returns the index around which the ...
Reference - What does this error mean in PHP?
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Notice: Undefined Index
Happens when you try to access an array by a key that does not exist in the array.
A typical example of an Undefined Index notice would be (demo)
$data = array('foo' => '42', 'bar');
echo $data['spinach'];
echo $...
SQL Joins Vs SQL Subqueries (Performance)?
...THINGS SQL though, your mileage may vary. The speed will depend a lot on indexes (do you have indexes on both ID columns? That will help a lot...) among other things.
The only REAL way to tell with 100% certainty which is faster is to turn on performance tracking (IO Statistics is especially use...
Deploying just HTML, CSS webpage to Tomcat
...he html file, which you want to be the starting page for your application, index.html
Start tomcat and point your browser to url "http://localhost:8080/MyApp". Your index.html page will pop up in the browser
share
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Stashing only staged changes in git - is it possible?
... STASH
Stage all your files that you need to stash.
Run git stash --keep-index. This command will create a stash with ALL of your changes (staged and unstaged), but will leave the staged changes in your working directory (still in state staged).
Run git stash push -m "good stash"
Now your "good st...
Add new row to dataframe, at specific row-index, not appended?
... 17
3 3 8 13 18
4 1 2 3 4
41 4 9 14 19
5 5 10 15 20
(Note we index r differently).
And finally, benchmarks:
library(microbenchmark)
microbenchmark(
rbind(existingDF[1:r,],newrow,existingDF[-(1:r),]),
insertRow(existingDF,newrow,r)
)
Unit: microseconds
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Accessing members of items in a JSONArray with Java
...; jsonItems = IntStream.range(0, jsonArray.length())
.mapToObj(index -> (JSONObject) jsonArray.get(index))
.collect(Collectors.toList());
// you can access the array elements now
jsonItems.forEach(arrayElement -> System.out.println(arrayElement.get("a")));
...