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Factors in R: more than an annoyance?
...y they are useful because model fitting packages like lme4 use factors and ordered factors to differentially fit models and determine the type of contrasts to use. And graphing packages also use them to group by. ggplot and most model fitting functions coerce character vectors to factors, so the res...
MySQL, update multiple tables with one query
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Take the case of two tables, Books and Orders. In case, we increase the number of books in a particular order with Order.ID = 1002 in Orders table then we also need to reduce that the total number of books available in our stock by the same number in Books table.
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Sorting a vector of custom objects
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Edit2: As Kappa suggests you can also sort the vector in the descending order by overloading a > operator and changing call of sort a bit:
struct MyStruct
{
int key;
std::string stringValue;
MyStruct(int k, const std::string& s) : key(k), stringValue(s) {}
bool operator...
PhantomJS failing to open HTTPS site
...ding the option after the script name didn't work - you need to call it in order: phantomjs --ignore-ssl-errors=yes script.js
– simonlchilds
Jan 16 '14 at 20:15
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Load local JSON file into variable
... Just a tip: you can use a json validator like jsonlint.com in order to check your json data before using it.
– Marco Panichi
Nov 7 '17 at 7:29
add a comment
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Do while loop in SQL Server 2008
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This seems like a copy-paste-reorder from stackoverflow.com/a/46362450/8239061.
– SecretAgentMan
Jul 11 '19 at 16:23
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Error handling with node.js streams
...ansform stream mechanics and calling its callback done with an argument in order to propagate the error:
var transformStream1 = new stream.Transform(/*{objectMode: true}*/);
transformStream1.prototype._transform = function (chunk, encoding, done) {
//var stream = this;
try {
// Do your tr...
How can I implement an Access Control List in my Web MVC application?
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Highly active question. Earn 10 reputation in order to answer this question. The reputation requirement helps protect this question from spam and non-answer activity.
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What is the best way to get all the divisors of a number?
...s about killing performance. Problem two: the divisors are not returned in order.
– Tomasz Gandor
Dec 10 '14 at 14:37
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What is the difference between atomic and critical in OpenMP?
...d. We are referring to those cases that synchronization is necessary.
In order to synchronize the threads in a multi-threaded program, we'll use lock. When the access is required to be restricted by only one thread at a time, locks come into play. The lock concept implementation may vary from proc...