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What is the difference between map and flatMap and a good use case for each?
... values from those that return a Some:
val rdd = sc.parallelize(Seq(1,2,3,4))
def myfn(x: Int): Option[Int] = if (x <= 2) Some(x * 10) else None
rdd.flatMap(myfn).collect
res3: Array[Int] = Array(10,20)
(noting here that an Option behaves rather like a list that has either one element, ...
How to delete items from a dictionary while iterating over it?
...over it:
>>> mydict = {'one': 1, 'two': 2, 'three': 3, 'four': 4}
>>> for k, v in mydict.iteritems():
... if k == 'two':
... del mydict[k]
...
------------------------------------------------------------
Traceback (most recent call last):
File "<ipython console>...
How do you print out a stack trace to the console/log in Cocoa?
...
547
NSLog(@"%@",[NSThread callStackSymbols]);
This code works on any thread.
...
Check orientation on Android phone
...3
AlexS
54544 silver badges1919 bronze badges
answered May 9 '10 at 20:06
hackbodhackbod
...
What is the MySQL VARCHAR max size?
...he limit is lower if you use a multi-byte character set like utf8 or utf8mb4.
Use TEXT types inorder to overcome row size limit.
The four TEXT types are TINYTEXT, TEXT, MEDIUMTEXT, and LONGTEXT. These correspond to the four BLOB types and have the same maximum lengths and storage requirements.
...
Joining two lists together
... |
edited Sep 28 '16 at 14:16
Sipo
2,68333 gold badges2222 silver badges5050 bronze badges
answered Oct...
Site stopped working in asp.net System.Web.WebPages.Razor.Configuration.HostSection cannot be cast t
...y name="System.Web.WebPages.Razor"
publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0"/>
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856a...
Keyboard shortcut to change font size in Eclipse?
...
Eclipse Neon (4.6)
Zoom In
Ctrl++
or
Ctrl+=
Zoom Out
Ctrl+-
This feature is described here:
In text editors, you can now use Zoom In (Ctrl++ or Ctrl+=) and Zoom Out (Ctrl+-) commands to increase and decrease the font size.
...
Parse JSON String into a Particular Object Prototype in JavaScript
...
answered May 15 '17 at 10:44
Erik van VelzenErik van Velzen
4,55733 gold badges1818 silver badges1717 bronze badges
...
pip issue installing almost any library
...r interpreter. See for example https://news.ycombinator.com/item?id=13539034, http://pyfound.blogspot.ca/2017/01/time-to-upgrade-your-python-tls-v12.html and https://bugs.python.org/issue17128.
Update Feb 2019:
For some it may be sufficient to upgrade pip. If the above error prevents you from doin...