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How to convert a java.util.List to a Scala list
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import scala.collection.JavaConversions._
will do implicit conversion for you; e.g.:
var list = new java.util.ArrayList[Int](1,2,3)
list.foreach{println}
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Check whether an array is empty [duplicate]
...pty($errors)) {
}
array_filter() function's default behavior will remove all values from array which are equal to null, 0, '' or false.
Otherwise in your particular case empty() construct will always return true if there is at least one element even with "empty" value.
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Difference between map, applymap and apply methods in Pandas
Can you tell me when to use these vectorization methods with basic examples?
10 Answers
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Bogus foreign key constraint fail
...each query (bugs.mysql.com/bug.php?id=8280), making it neccessary to write all the drop statements in one query, eg.
SET FOREIGN_KEY_CHECKS=0;
DROP TABLE my_first_table_to_drop;
DROP TABLE my_second_table_to_drop;
SET FOREIGN_KEY_CHECKS=1;
Where the SET FOREIGN_KEY_CHECKS=1 serves as an extr...
How can I find the length of a number?
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This solution would not work with large number or small number that has more than 20 digits. eg. 1.2e+22 toString().length outputs 7
– CherylG
Oct 18 '16 at 0:52
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What do the f and t commands do in Vim?
... information but people keep telling me that they are very useful. Would really appreciate an answer with an example if possible, thanks!
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Why do most C developers use define instead of const? [duplicate]
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@C. Ross: Consistency. All manifest constants are usually defined with #defines. const is only used to indicate a read-only (access path to a) variable. I know, const in C is just plain broken :-)
– Bart van Ingen Schenau
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PHP function to get the subdomain of a URL
...hen dealing with co.uk, for example, it does not. As seen here This is actually a harder problem to solve.
– Mike Lewis
Mar 13 '11 at 23:12
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What is the difference between `throw new Error` and `throw someObject`?
...t what we can extract from it in an event of an error? The Error object in all browsers support the following two properties:
name: The name of the error, or more specifically, the name of the constructor function the error belongs to.
message: A description of the error, with this description var...
What ports does RabbitMQ use?
What ports does RabbitMQ Server use or need to have open on the firewall for a cluster of nodes?
4 Answers
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