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Quicksort: Choosing the pivot
... asserted:
'Median of 3' is NOT first last middle. Choose three random indexes, and take the middle value of this. The whole point is to make sure that your choice of pivots is not deterministic - if it is, worst case data can be quite easily generated.
To which I responded:
Analysis Of Hoar...
How to test multiple variables against a value?
...)
nums = [add numbers here]
letters = [add corresponding letters here]
for index in range(len(nums)):
for obj in list:
if obj == num[index]:
MyList.append(letters[index])
break
You can also put the numbers and letters in a dictionary and do it, but this is proba...
Is mongodb running?
I have installed mongodb and the php drivers on my unix server.
9 Answers
9
...
How Can I Download a File from EC2 [closed]
... @gideon That definitively should work as expected (i.e. recursively copy all files from /srv/www/myapp/ to the local machine). Wild guess - are you running scp from your ec2 server perhaps? If yes, you need to run it from your local machine (i.e. the machine you want to copy files to).
...
Omitting the second expression when using the if-else shorthand
...o an option:
x==2 && dosomething();
dosomething() will only be called if x==2 is evaluated to true. This is called Short-circuiting.
It is not commonly used in cases like this and you really shouldn't write code like this. I encourage this simpler approach:
if(x==2) dosomething();
You...
Fix a Git detached head?
...e you have changed a file and want to restore it to the state it is in the index, don't delete the file first, just do
git checkout -- path/to/foo
This will restore the file foo to the state it is in the index.
If you want to keep your changes associated with the detached HEAD
Run git branch tmp -...
git: Show index diff in commit message as comment
...t;..." to unstage)
#
# modified: README
#
diff --git a/README b/README
index af5626b..c62237e 100644
--- a/README
+++ b/README
@@ -1 +1 @@
-Hello, world!
+Goodbye, world!
(note the lack of # preceding the diff lines)
And then the actual commit message:
$ git log -n 1
commit ad21a2655ef6d8173...
How is Python's List Implemented?
...
It's a dynamic array. Practical proof: Indexing takes (of course with extremely small differences (0.0013 µsecs!)) the same time regardless of index:
...>python -m timeit --setup="x = [None]*1000" "x[500]"
10000000 loops, best of 3: 0.0579 usec per loop
...&...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...il='a@b.com', data='inserted data')
stmt = stmt.on_conflict_do_update(
index_elements=[my_table.c.user_email],
index_where=my_table.c.user_email.like('%@gmail.com'),
set_=dict(data=stmt.excluded.data)
)
conn.execute(stmt)
http://docs.sqlalchemy.org/en/latest/dialects/postgresql.htm...
What is BSON and exactly how is it different from JSON?
...sing BSON encoding on top of JSON, MongoDB gets the capability of creating indexes on top of values that resides inside the JSON document in raw format. This helps in running efficient analytical queries as NoSQL system were known for having no support for Indexes.
...