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Undefined method 'task' using Rake 0.9.0
I just updated Rake to the latest version ( 0.9.0.beta.4 ) and the rake command ends up with the following error message:
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Gray out image with CSS?
What's the best way (if any) to make an image appear "grayed out" with CSS (i.e., without loading a separate, grayed out version of the image)?
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What's the (hidden) cost of Scala's lazy val?
One handy feature of Scala is lazy val , where the evaluation of a val is delayed until it's necessary (at first access).
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Apply pandas function to column to create multiple new columns?
How to do this in pandas:
13 Answers
13
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Converting RGB to grayscale/intensity
When converting from RGB to grayscale, it is said that specific weights to channels R, G, and B ought to be applied. These weights are: 0.2989, 0.5870, 0.1140.
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How do you check whether a number is divisible by another number (Python)?
I need to test whether each number from 1 to 1000 is a multiple of 3 or a multiple of 5. The way I thought I'd do this would be to divide the number by 3, and if the result is an integer then it would be a multiple of 3. Same with 5.
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Semi-transparent color layer over background-image?
I have a DIV and I would like to put a pattern as background. This pattern is gray. So to make it a little more nice, I would like to put a light transparent color "layer" over. Below is what I tried but which did not work. Is there a way to put the colored layer over the background image?
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A weighted version of random.choice
I needed to write a weighted version of random.choice (each element in the list has a different probability for being selected). This is what I came up with:
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Django Server Error: port is already in use
Restarting the Django server displays the following error:
16 Answers
16
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Email Address Validation in Android on EditText [duplicate]
How can we perform Email Validation on edittext in android ? I have gone through google & SO but I didn't find out a simple way to validate it.
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