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How do I completely uninstall Node.js, and reinstall from beginning (Mac OS X)
My version of node is always v0.6.1-pre even after I install brew node and NVM install v0.6.19.
28 Answers
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Summarizing multiple columns with dplyr? [duplicate]
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The dplyr package contains summarise_all for this aim:
library(dplyr)
df %>% group_by(grp) %>% summarise_all(list(mean))
#> # A tibble: 3 x 5
#> grp a b c d
#> <int> <dbl> <dbl> <dbl> <dbl>
#>...
How to implement has_many :through relationships with Mongoid and mongodb?
...uire multiple queries.
https://github.com/mongoid/mongoid/issues/544
Normally if you have a many-many relationship in a RDBMS you would model that differently in MongoDB using a field containing an array of 'foreign' keys on either side. For example:
class Physician
include Mongoid::Document
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How can I run a PHP script in the background after a form is submitted?
...f subscribers and send out 150+ emails. (The emails are being sent individually as requested by the system administrators of our email server because of mass email policies.)
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android asynctask sending callbacks to ui [duplicate]
...tivity I'm initializing the asynctask, and I want the asynctask to report callbacks back to my activity.
Is it possible? Or does the asynctask must be in the same class file as the activity?
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SQL Server 2008 can't login with newly created user
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SQL Server was not configured to allow mixed authentication.
Here are steps to fix:
Right-click on SQL Server instance at root of Object Explorer, click on Properties
Select Security from the left pane.
Select the SQL Server and Windows Authentication m...
Reading a plain text file in Java
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I'd also recommend you download and read this wonderful (yet free) book called Thinking In Java
In Java 7:
new String(Files.readAllBytes(...))
(docs)
or
Files.readAllLines(...)
(docs)
In Java 8:
Files.lines(..).forEach(...)
(docs)
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How do I get the currently displayed fragment?
...t the currently displayed Fragment instance, not iteratively check through all fragments and then decide which fragment is now displayed on the screen. I think your answer needs my code to iteratively check each of my fragments, and find out the visible one ...
– Leem.fin
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Hyphen, underscore, or camelCase as word delimiter in URIs?
...designing an HTTP-based API for an intranet app. I realize it's a pretty small concern in the grand scheme of things, but: should I use hyphens, underscores, or camelCase to delimit words in the URIs?
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Filter dataframe rows if value in column is in a set list of values [duplicate]
... regular expressions.
For example, if we want to return a DataFrame where all of the stock IDs which begin with '600' and then are followed by any three digits:
>>> rpt[rpt['STK_ID'].str.contains(r'^600[0-9]{3}$')] # ^ means start of string
... STK_ID ... ...