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Apache Spark: map vs mapPartitions?
...language engine that will process the map task. (I'm in R, which may have more startup overhead.) If you would be performing multiple operations, then mapPartitions seems to be quite a bit faster -- I'm assuming this is because it reads the RDD only once. Even if the RDD is cached in RAM, that sa...
How do you do relative time in Rails?
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How do you overcome the HTML form nesting limitation?
...gt; or <button> elements is irrelevant, although buttons are usually more appropriate for toolbars, as you say. By the way, button elements have not been supported by all the browsers for 15 years.
– shovavnik
Dec 15 '12 at 13:56
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Best Practice: Access form elements by HTML id or name attribute?
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How to echo or print an array in PHP?
...;'; print_r($array); echo '</pre>';
2) use var_dump($array) to get more information of the content in the array like datatype and length.
3) you can loop the array using php's foreach(); and get the desired output. more info on foreach in php's documentation website:
http://in3.php.net/manu...
Map implementation with duplicate keys
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How to add a custom loglevel to Python's logging facility
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Certainly much more informative than the current answer.
– Mad Physicist
Feb 29 '16 at 15:31
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How can I add a column that doesn't allow nulls in a Postgresql database?
...lue for existing rows. j_random_hacker's answer allows for that, making it more robust.
– jpmc26
May 5 '16 at 23:51
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Generating an MD5 checksum of a file
...ferent bunch of letters is all. It's not that hard.
Here is a way that is more complex, but memory efficient:
import hashlib
def hash_bytestr_iter(bytesiter, hasher, ashexstr=False):
for block in bytesiter:
hasher.update(block)
return hasher.hexdigest() if ashexstr else hasher.dig...
Convert String to Float in Swift
...h Swift 2.0 you can just use Float(Wage.text) which returns a Float? type. More clear than the below solution which just returns 0.
If you want a 0 value for an invalid Float for some reason you can use Float(Wage.text) ?? 0 which will return 0 if it is not a valid Float.
Old Solution
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