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urlencode vs rawurlencode?
If I want to create a URL using a variable I have two choices to encode the string. urlencode() and rawurlencode() .
11 ...
PSQLException: current transaction is aborted, commands ignored until end of transaction block
...tarted using Postgres... it's really annoying that Postgres does this, and now we have to be really rewrite a big bulk of our program that we are porting from Oracle to Postgres. Why isn't there an option like the first to make it behave like Oracle but without the auto-commit?
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Convert a row of a data frame to vector
...tly more explicit way to get to the same result.
As @Josh comments below, if you have a not-completely-numeric (alphabetic, factor, mixed ...) data frame, you need as.character(df[1,]) instead.
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Hidden Features of Java
...d it, never heard of it before.
ThreadLocals are typically not so widely known as a way to store per-thread state.
Since JDK 1.5 Java has had extremely well implemented and robust concurrency tools beyond just locks, they live in java.util.concurrent and a specifically interesting example is the j...
How do I change selected value of select2 dropdown with JqGrid?
...irst I initialize select2 on my select:
$('#my-best-friend').select2();
Now I manually select Bob in the browser. Next Bob does something naughty and I don't like him anymore. So the system unselects Bob for me:
$('#my-best-friend').val('').trigger('change');
Or say I make the system select th...
How can I rename a field for all documents in MongoDB?
...ll your records.
Or you can use the former way:
remap = function (x) {
if (x.additional){
db.foo.update({_id:x._id}, {$set:{"name.last":x.name.additional}, $unset:{"name.additional":1}});
}
}
db.foo.find().forEach(remap);
In MongoDB 3.2 you can also use
db.students.updateMany( {}, { $r...
Escaping regex string
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Return string with all non-alphanumerics backslashed; this is useful if you want to match an arbitrary literal string that may have regular expression metacharacters in it.
A simplistic example, search any occurence of the provided string optionally followed by 's', and return the match obje...
How to convert Set to Array?
....forEach(v => array.push(v));
Previously, using the non-standard, and now deprecated array comprehension syntax:
let array = [v for (v of mySet)];
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How to get line count of a large file cheaply in Python?
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num_lines = sum(1 for line in open('myfile.txt') if line.rstrip()) for filter empty lines
– Honghe.Wu
Mar 3 '14 at 9:26
62
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Android Writing Logs to text File
... and Android logging
Log4j is generic java logging implementation and is now a project of
Apache software foundation. It is not Android specific and so has
some incompatibilities with Android.
SL4J is not a logging implementation, It is an abstraction layer. It
helps avoid a situations like, each...