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Append column to pandas dataframe
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@BenDundee Join and concat use a lot of the same code under the hood, so the "right" way probably only matters when you consider edge cases. For instance here if both DataFrames had a 'data' column the join would fail, whereas a concat would...
django unit tests without a db
... db? I want to test business logic which doesn't require the db to set up. And while it is fast to setup a db, I really don't need it in some situations.
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Why can't C++ be parsed with a LR(1) parser?
I was reading about parsers and parser generators and found this statement in wikipedia's LR parsing -page:
6 Answers
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Convert a binary NodeJS Buffer to JavaScript ArrayBuffer
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Instances of Buffer are also instances of Uint8Array in node.js 4.x and higher. Thus, the most efficient solution is to access the buf.buffer property directly, as per https://stackoverflow.com/a/31394257/1375574. The Buffer constructor also takes an ArrayBufferView argument if you need to ...
What is the purpose of setting a key in data.table?
I am using data.table and there are many functions which require me to set a key (e.g. X[Y] ). As such, I wish to understand what a key does in order to properly set keys in my data tables.
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How do I empty an array in JavaScript?
Is there a way to empty an array and if so possibly with .remove() ?
18 Answers
18
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Differences between detach(), hide() and remove() - jQuery
... the DOM completely.
detach() is like remove(), but keeps the stored data and events associated with the matched elements.
To re-insert a detached element into the DOM, simply insert the returned jQuery set from detach():
var span = $('span').detach();
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span.appendTo('body');
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Can you use a trailing comma in a JSON object?
...ed to worry about all browsers.
In general I try turn the problem around, and add the comma before the actual value, so you end up with code that looks like this:
s.append("[");
for (i = 0; i < 5; ++i) {
if (i) s.append(","); // add the comma only if this isn't the first entry
s.appendF("\"...
How do I get the AM/PM value from a DateTime?
... answered Oct 24 '11 at 12:06
AndyAndy
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How to move files from one git repo to another (not a clone), preserving history
...ory, since you wanted to end up with only a (renamed) subset of the files, and this by definition changes the hashes. Since none of the standard commands (e.g. pull) rewrite history, there's no way you could use them to accomplish this.
You could refine the details, of course - some of your cloning...