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How to get the last N rows of a pandas DataFrame?
... dataframe df1 and df2 (df1 is vanila dataframe, df2 is indexed by 'STK_ID' & 'RPT_Date') :
3 Answers
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How does one unit test routes with Express?
...rocess of learning Node.js and have been playing around with Express . Really like the framework;however, I'm having trouble figuring out how to write a unit/integration test for a route.
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What is the difference between map and flatMap and a good use case for each?
...ark-shell session:
First, some data - two lines of text:
val rdd = sc.parallelize(Seq("Roses are red", "Violets are blue")) // lines
rdd.collect
res0: Array[String] = Array("Roses are red", "Violets are blue")
Now, map transforms an RDD of length N into another RDD of length N.
For examp...
How can I check if an ip is in a network in Python?
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Additionally, struct.unpack('L',socket.inet_aton(ip))[0] will fail on architectures where 'L' unpacks to something different than 4 bytes, regardless of endianness.
– Rafał Dowgird
May 4 '09 at...
Download multiple files with a single action
... don't portably parse multipart responses from the server side, but technically there's nothing difficult with doing this.
– CMCDragonkai
Jul 27 '18 at 4:25
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Hidden Features of C#? [closed]
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This isn't C# per se, but I haven't seen anyone who really uses System.IO.Path.Combine() to the extent that they should. In fact, the whole Path class is really useful, but no one uses it!
I'm willing to bet that every production app has the following code, even though it shoul...
What are unit tests, integration tests, smoke tests, and regression tests?
...re we just check that when the system under test is invoked it returns normally and does not blow up.
Smoke testing is both an analogy with electronics, where the first test occurs when powering up a circuit (if it smokes, it's bad!)...
... and, apparently, with plumbing, where a system of pipes i...
Database sharding vs partitioning
...databases. Sharding is one specific type of partitioning, part of what is called horizontal partitioning.
Here you replicate the schema across (typically) multiple instances or servers, using some kind of logic or identifier to know which instance or server to look for the data. An identifier of th...
Rails: How does the respond_to block work?
...html
The Responder does NOT contain a method for .html or .json, but we call these methods anyways! This part threw me for a loop.
Ruby has a feature called method_missing. If you call a method that doesn't exist (like json or html), Ruby calls the method_missing method instead.
http://ruby-meta...
Easiest way to open a download window without navigating away from the page
...ment will be loaded using the URL as if window.location.assign() had been called with the modified URL” - developer.mozilla.org/en-US/docs/Web/API/window.location
– Rob Juurlink
Aug 19 '13 at 11:47
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