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Mean per group in a data.frame [duplicate]
I have a data.frame and I need to calculate the mean per group (i.e. per Month , below).
8 Answers
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Unittest setUp/tearDown for several tests
... is fired at the beginning/end of a scenario of tests? The functions setUp and tearDown are fired before/after every single test.
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NoSQL (MongoDB) vs Lucene (or Solr) as your database
... similarity with how to treat items as "Documents", just like Lucene does (and users of Solr).
10 Answers
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How to create a windows service from java app
...inherited a java application that needs to be installed as a service on XP and vista. It's been about 8 years since I've used windows in any form and I've never had to create a service, let alone from something like a java app (I've got a jar for the app and a single dependency jar - log4j). What i...
Scatter plot and Color mapping in Python
I have a range of points x and y stored in numpy arrays.
Those represent x(t) and y(t) where t=0...T-1
3 Answers
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iOS Safari – How to disable overscroll but allow scrollable divs to scroll normally?
I'm working on an iPad-based web app, and need to prevent overscrolling so that it seems less like a web page. I'm currently using this to freeze the viewport and disable overscroll:
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To ARC or not to ARC? What are the pros and cons? [closed]
...ge collection. It has no GC runtime overhead. The compiler inserts retains and releases in all the places you should have anyway. But it's smarter than you and can optimize out the ones that aren't actually needed (just like it can unroll loops, eliminate temporary variables, inline functions, etc.)...
How Can I Browse/View The Values Stored in Redis [closed]
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Windows and OS X binaries now require a subscription.
– Somantra
Dec 18 '18 at 17:55
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Build an iOS app without owning a mac? [closed]
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iPhone/iPad (iOS) app development
iPhone/iPad (iOS) app development and Publish to iTunes Store
1. iPhone/iPad (iOS) app development
So If you just want to develop iOS apps you don't want to pay anything,
You just need Mac + XCode IDE
Get Mac Mini or Mac Machine
Create Developer Accoun...
Python string prints as [u'String']
...duces Unicode. So you need to convert the list to a single unicode string, and then convert that to ASCII.
I don't know exaxtly how you got the one-element lists; the contents member would be a list of strings and tags, which is apparently not what you have. Assuming that you really always get a li...