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How do I make a transparent canvas in html5?
How can I make a canvas transparent? I need to because I want to put two canvases on top of one another.
6 Answers
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Rails how to run rake task
How do I run this rake file in terminal/console?
6 Answers
6
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What does |= (single pipe equal) and &=(single ampersand equal) mean
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They're compound assignment operators, translating (very loosely)
x |= y;
into
x = x | y;
and the same for &. There's a bit more detail in a few cases regarding an implicit cast, and the target variable is only evaluated once, b...
Convert numpy array to tuple
Note: This is asking for the reverse of the usual tuple-to-array conversion.
5 Answers
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How to create a loop in bash that is waiting for a webserver to respond?
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Combining the question with chepner's answer, this worked for me:
until $(curl --output /dev/null --silent --head --fail http://myhost:myport); do
printf '.'
sleep 5
done
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What's the difference between the build and create methods in FactoryGirl?
The Factory Girl introduction delineates the difference between FactoryGirl.build() and FactoryGirl.create() :
3 Answer...
Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
I am working with the pandas library and I want to add two new columns to a dataframe df with n columns (n > 0).
These new columns result from the application of a function to one of the columns in the dataframe.
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How long is the SHA256 hash?
I'm going to run SHA256 on a password + salt, but I don't know how long to make my VARCHAR when setting up the MySQL database. What is a good length?
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initializing a boolean array in java
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I just need to initialize all the array elements to Boolean false.
Either use boolean[] instead so that all values defaults to false:
boolean[] array = new boolean[size];
Or use Arrays#fill() to fill the entire array with B...
NSLog/printf specifier for NSInteger?
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Updated answer:
You can make use of the z and t modifiers to handle NSInteger and NSUInteger without warnings, on all architectures.
You want to use %zd for signed, %tu for unsigned, and %tx for hex.
This information comes...