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cartesian product in pandas

...n unused column name, then add dummy columns with that name, merge, and finally drop the column on the result? Creating, as opposed to reading, data with pandas is just a pain – Bananach Oct 10 '19 at 7:31 ...
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Setting variable to NULL after free

... int *nPtr=NULL;. Now, I would agree that this would be redundant, with a malloc following right in the next line. However, if there is code between the declaration and the first initialization, somebody might start using the variable even though it has no value yet. If you null-initialize, you get ...
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How do I create a Java string from the contents of a file?

... Read all text from a file Java 11 added the readString() method to read small files as a String, preserving line terminators: String content = Files.readString(path, StandardCharsets.US_ASCII); For versions between Java 7 and 11,...
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Send and receive messages through NSNotificationCenter in Objective-C?

... @implementation TestClass - (void) dealloc { // If you don't remove yourself as an observer, the Notification Center // will continue to try and send notification objects to the deallocated // object. [[NSNotificationCenter defaultCenter] removeO...
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The preferred way of creating a new element with jQuery

... I personally think that it's more important for the code to be readable and editable than performant. Whichever one you find easier to look at and it should be the one you choose for above factors. You can write it as: $('#box').ap...
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What's the Linq to SQL equivalent to TOP or LIMIT/OFFSET?

... Technically, the questioner asked for Linq to SQL, so VB is a viable assumption. That said, ALassek, i'm a c# guy myself and prefer your answer. :-) – David Alpert Oct 10 '08 at 16:51 ...
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Parsing a string into a boolean value in PHP

...urned only for "0", "false", "off", "no", and "", and NULL is returned for all non-boolean values. share | improve this answer | follow | ...
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How can I autoplay a video using the new embed code style for Youtube?

... The first parameter after the video ID needs to start with "?" ,all parameters AFTER that needs to be added with "&". If you had for example "?rel=0&autoplay=1" it would be the same as "?autoplay=1&rel=0" and they would both work. – Thanos ...
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When to use reinterpret_cast?

...time hence the word static . This is the cast the C++ compiler uses internally for implicit casts also. 11 Answers ...
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How do I efficiently iterate over each entry in a Java Map?

...erret The only reason you might want to use an iterator is if you need to call its remove method. If that is the case, this other answer shows you how to do it. Otherwise, the enhanced loop as shown in the answer above is the way to go. – assylias Oct 8 '12 at ...