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typeof !== “undefined” vs. != null

...n the two. In many cases, == can be better, because it tests for both null and undefined. – seanmonstar Jun 19 '12 at 16:58 10 ...
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Scatterplot with too many points

...+ geom_point(alpha = 0.3) Another convenient way to deal with this is (and probably more appropriate for the number of points you have) is hexagonal binning: ggplot(df,aes(x=x,y=y)) + stat_binhex() And there is also regular old rectangular binning (image omitted), which is more like your tr...
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Laravel migration: unique key is too long, even if specified

...l', 250); Which is the default, actually: $table->string('email'); And you should be good. For Laravel 5.4 you can find a solution in this Laravel 5.4: Specified key was too long error, Laravel News post: As outlined in the Migrations guide to fix this all you have to do is edit your AppSe...
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What are conventions for filenames in Go?

...re ignored by the go tool Files with the suffix _test.go are only compiled and run by the go test tool. Files with os and architecture specific suffixes automatically follow those same constraints, e.g. name_linux.go will only build on linux, name_amd64.go will only build on amd64. This is the same ...
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How to configure static content cache per folder and extension in IIS7?

...ned mostly from the IIS.NET config reference site: iis.net/ConfigReference and from poking about the %systemroot%\system32\inetsrv\config\applicationhost.config file and related friends. – Kev Nov 9 '11 at 18:11 ...
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How do I get the path of the current executed file in Python?

...always loaded from a file. If you create a module with the following code and put it in the same directory as your main script, then the main script can import the module and use that to locate itself. some_path/module_locator.py: def we_are_frozen(): # All of the modules are built-in to the ...
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Given a view, how do I get its viewController?

...r, because that would break MVC principles. The controller, on the other hand, knows which view it's responsible for (self.view = myView), and usually, this view delegates methods/events for handling to the controller. Typically, instead of a pointer to your view, you should have a pointer to your...
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How do I retrieve the number of columns in a Pandas data frame?

How do you programmatically retrieve the number of columns in a pandas dataframe? I was hoping for something like: 6 Answer...
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Adding local .aar files to Gradle build using “flatDirs” is not working

...tions (under edit) (File -> New-> New Module -> Import .JAR/.AAR) and import your .AAR. Then in your project build.gradle (not the top level one, the one under 'app') add the following (in the dependencies section): dependencies { compile project(':Name-Of-Your-Project') } Note Nam...
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How to downgrade or install an older version of Cocoapods

...s you can install a specific version of cocoa pods via the following command: sudo gem install cocoapods -v 0.25.0 You can use older installed versions with following command: pod _0.25.0_ setup share | ...