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Importing data from a JSON file into R
..."startPrice" "lastVote.timestamp" "lastVote.user.name" "lastVote.user.user_id"
> winners[,c("winner","startPrice","lastVote.user.name")]
winner startPrice lastVote.user.name
1 68694999 0 Lamur
> winners[,c("votes")]
[[1]]
ts user.name user....
How do I parallelize a simple Python loop?
...fset)))
Note that this won't work in the interactive interpreter.
To avoid the usual FUD around the GIL: There wouldn't be any advantage to using threads for this example anyway. You want to use processes here, not threads, because they avoid a whole bunch of problems.
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belongs_to through associations
...tion cannot have a :through option. You're better off caching the question_id on Choice and adding a unique index to the table (especially because validates_uniqueness_of is prone to race conditions).
If you're paranoid, add a custom validation to Choice that confirms that the answer's question_id ...
Android: textColor of disabled button in selector not showing?
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You need to also create a ColorStateList for text colors identifying different states.
Do the following:
Create another XML file in res\color named something like text_color.xml.
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com...
Format of the initialization string does not conform to specification starting at index 0
...r 2012
Standard Security
Server=myServerAddress;Database=myDataBase;User Id=myUsername;Password=myPassword;
Trusted Connection
Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;
Connection to a SQL Server instance
The server/instance name syntax used in the server option is ...
How do I convert a Django QuerySet into list of dicts?
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Use the .values() method:
>>> Blog.objects.values()
[{'id': 1, 'name': 'Beatles Blog', 'tagline': 'All the latest Beatles news.'}],
>>> Blog.objects.values('id', 'name')
[{'id': 1, 'name': 'Beatles Blog'}]
Note: the result is a QuerySet which mostly behaves like a list...
Using margin:auto to vertically-align a div
...now, so just use that, as per this answer.
You can't use:
vertical-align:middle because it's not applicable to block-level elements
margin-top:auto and margin-bottom:auto because their used values would compute as zero
margin-top:-50% because percentage-based margin values are calculated relative t...
How to launch an Activity from another Application in Android
I want to launch an installed package from my Android application. I assume that it is possible using intents, but I didn't find a way of doing it. Is there a link, where to find the information?
...
Changing CSS Values with Javascript
...'s easy to set inline CSS values with javascript. If I want to change the width and I have html like this:
9 Answers
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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
... work for me, but it seems to only work as shown above if one set contains identically matching rows of the other set. Consider this case: a2 <- data.frame(a = c(1:3, 1), b = c(letters[1:3], "c")). Leave a1 the same. Now try the comparison. It's not clear to me even in reading the options what th...