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How to make a background 20% transparent on Android
...w this procedure:
Given a transparency percentage, for example 20%, you know the opaque percentage value is 80% (this is 100-20=80)
The range for the alpha channel is 8 bits (2^8=256), meaning the range goes from 0 to 255.
Project the opaque percentage into the alpha range, that is, multiply the r...
How to reshape data from long to wide format
...s this simply, with gather()/spread() being the terms for melt/cast.
Edit: Now, in 2019, tidyr v 1.0 has launched and set spread and gather on a deprecation path, preferring instead pivot_wider and pivot_longer, which you can find described in this answer. Read on if you want a brief glimpse into th...
HTML5 Email Validation
...t. No need to specify the pattern (I just copied code from OP, I corrected now :) )
– Midhun MP
Oct 26 '13 at 11:01
6
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How to remove a single, specific object from a ConcurrentBag?
...d SynchronizedCollection is available in the Collections.Generic namespace now.
– Lucas Leblanc
Sep 25 '19 at 18:28
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Retrieve only the queried element in an object array in MongoDB collection
...y only return the array "shapes" and it won't return other fields. Anyone knows how to return other fields also?
– Mark Thien
Jul 29 '16 at 0:24
1
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What does bundle exec rake mean?
...
I have not used bundle exec much, but am setting it up now.
I have had instances where the wrong rake was used and much time wasted tracking down the problem. This helps you avoid that.
Here's how to set up RVM so you can use bundle exec by default within a specific project d...
YouTube Video Embedded via iframe Ignoring z-index?
...ost), appending just ?wmode=transparent as a new query string to the URL.
Now, regardless of what may or may not be on the end of the YouTube URL as a query string already, it gets preserved, and the required wmode parameters get injected or added without damage to what was there before.
Here's th...
Maven build failed: “Unable to locate the Javac Compiler in: jre or jdk issue”
... on the web, it looks like the Maven uses JAVA_HOME, but the Maven Plugin knows nothing about JAVA_HOME and instead defaults to the VM used to start Eclipse.
– jnosek
Jul 14 '11 at 15:18
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How do I update pip itself from inside my virtual environment?
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This is now what pip itself recommends, if it detects a newer version of itself.
– tephyr
May 29 '16 at 21:51
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How does a hash table work?
...u need them.
So, you decide that if the person that wants to read a book knows the title of the book and the exact title to boot, then that's all it should take. With the title, the person, with the aid of the librarian, should be able to find the book easily and quickly.
So, how can you do that? ...