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Useful code which uses reduce()? [closed]
...uses reduce() function in python? Is there any code other than the usual + and * that we see in the examples?
24 Answers
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In SQL, what's the difference between count(column) and count(*)?
...a values(null,1)
insert #bla values(1,null)
insert #bla values(null,null)
select count(*),count(id),count(id2)
from #bla
results
7 3 2
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Maven error: Could not find or load main class org.codehaus.plexus.classworlds.launcher.Launcher
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I hit this problem too, and found this article. For Maven3, changing my environment variable name from M2_HOME to M3_HOME did the trick. I am on a Mac running OSX 10.9 with JDK 1.7. Hope this helps.
Note: Please delete M2_HOME, if already set. E...
How do you print out a stack trace to the console/log in Cocoa?
...his question was originally asked. For pre-Snow-Leopard, use the backtrace and backtrace_symbols functions; see the backtrace(3) manpage.
– Peter Hosey
Feb 25 '10 at 13:32
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How to turn off INFO logging in Spark?
I installed Spark using the AWS EC2 guide and I can launch the program fine using the bin/pyspark script to get to the spark prompt and can also do the Quick Start quide successfully.
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“405 method not allowed” in IIS7.5 for “PUT” method
...ick on "WebDAV".
5.Click on "Request Restrictions".
6.In the tab "Verbs" select "All verbs" .
7.Press OK.
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Ubuntu rails install fails on zlib
...0 as my dev box; it's my first serious foray into Linux as a daily-use OS, and I'm having a hard time getting Rails going. I have followed a number of tutorials which all seem to work fine, but when I try and use gem install or gem update on anything, I get an error that looks like this:
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Regex match everything after question mark?
... for something like this? Topics: code, programming, design So I want to select the colon and look behind as far as the cpaital T of topics and fowards to the end on the line? (in this case end of the line is "design".
– Mark
Dec 11 '10 at 21:36
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Is there a shortcut in Eclipse to Re-run the most recently launched program?
...running and debugging applications has been simplified to run or debug the selected file or active editor.
When the selected resource (or active editor) is not executable, users can opt to launch the associated project or re-launch the previous launch.
These settings are managed on the Run/D...
Select multiple records based on list of Id's with linq
I have a list containing Id's of my UserProfile table. How can i select all UserProfiles based on the list of Id's i got in a var using LINQ ?
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