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Count number of objects in list [closed]
...gh length() will also work (but it's a trick when your data.frame has only one column) :
> length (df)
[1] 30
> length (df[[1]])
[1] 2
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Core dump file analysis [duplicate]
...t need a binary (with debugging symbols included) that is identical to the one that generated the core dump file. Then you can run gdb path/to/the/binary path/to/the/core/dump/file to debug it.
When it starts up, you can use bt (for backtrace) to get a stack trace from the time of the crash. In the...
Removing MySQL 5.7 Completely [closed]
...mmand requires confirmation & if run as a block, the command below the one currently running will cancel the confirmation (leading to the command not being run).
Please refer to How do I uninstall Mysql?
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Convert List into Comma-Separated String
...in all of the elements using the string passed as the first parameter into one single string.
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Is an array an object in java
...stance of a class? If so, can I extend that class?
– One Two Three
Apr 3 '13 at 20:23
9
No, it do...
lsof survival guide [closed]
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One good way is to use the cheat gem, if you use Ruby. It's just convenient, community-driven CLI to cheat-sheets of many utilities (language independent). Give it a try.
– Kedar Mhaswade
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Razor comment syntax
...ed a new @* * syntax. So now there are three ways to comment. Not just the one by JarretV.
– Buildstarted
Nov 15 '10 at 17:26
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Performance of foreach, array_map with lambda and array_map with static function
...me dump, and they are called via array_map in much the same way, with just one exception: the closure call includes one more opcode DECLARE_LAMBDA_FUNCTION, which explains why using it is a bit slower than using the named function. Now, comparing the array loop vs array_map calls, everything in the...
Ruby : How to write a gem? [closed]
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Rubygems.org's Guides is one of the best resources for writing your own gem.
If you're using Bundler in your app, you might want to look at Ryan Bigg's guide to Developing a RubyGem using Bundler and the Railscast on creating gems with Bundler.
If ...
Any good boolean expression simplifiers out there? [closed]
...r simplifying boolean formula's when they get a bit more complex. Try this one: (((NOT C) AND (NOT A)) OR ((NOT B) AND (NOT C) AND (NOT D) AND (NOT A)) OR ((NOT B) AND (NOT C) AND D AND A) OR (B AND C AND (NOT D) AND (NOT A)) OR (B AND C AND D AND A))
– Albert Hendriks
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