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How do you represent a graph in Haskell?
... haskell using algebraic data types. But how would you go about typographically representing a graph? It seems that you need to have pointers. I'm guessing you could have something like
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Query grants for a table in postgres
How can I query all GRANTS granted to an object in postgres?
7 Answers
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What is “vectorization”?
...vec" instructions, and even some ARM chips have a vector instruction set, called NEON.
"Vectorization" (simplified) is the process of rewriting a loop so that instead of processing a single element of an array N times, it processes (say) 4 elements of the array simultaneously N/4 times.
(I chose 4...
Comparing date part only without comparing time in JavaScript
... that should give equal dates will not work because the two date are not really at 00:00:00:0.
– Oliver
Feb 8 '15 at 15:40
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innerText vs innerHTML vs label vs text vs textContent vs outerText
... a couple of differences:
Note that while textContent gets the content of all elements, including <script> and <style> elements, the mostly equivalent IE-specific property, innerText, does not.
innerText is also aware of style and will not return the text of hidden elements, whereas te...
How to flatten nested objects with linq expression
...used: http://odetocode.com/blogs/scott/archive/2008/03/25/inner-outer-lets-all-join-together-with-linq.aspx
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count the frequency that a value occurs in a dataframe column
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If you want to apply to all columns you can use:
df.apply(pd.value_counts)
This will apply a column based aggregation function (in this case value_counts) to each of the columns.
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How important is the order of columns in indexes?
... 3, the optimizer wouldn't even use the index, because it's not helpful at all in narrowing down the result sets. Anytime you're in a query, narrowing down the number of results to deal with before the next step means better performance.
Since the index is also stored this way, there's no backtrac...
Compare two List objects for equality, ignoring order [duplicate]
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If you want them to be really equal (i.e. the same items and the same number of each item), I think that the simplest solution is to sort before comparing:
Enumerable.SequenceEqual(list1.OrderBy(t => t), list2.OrderBy(t => t))
Edit:
Here is...
How to concatenate columns in a Postgres SELECT?
...catenated to NULL is NULL. If NULL values can be involved and the result shall not be NULL, use concat_ws() to concatenate any number of values (Postgres 9.1 or later):
SELECT concat_ws(', ', a, b) AS ab FROM foo;
Or concat() if you don't need separators:
SELECT concat(a, b) AS ab FROM foo;
No...