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Display image as grayscale using matplotlib
...olormap. I need the grayscale because I want to draw on top of the image with color.
7 Answers
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URLWithString: returns nil
it may be very easy, but I don't seems to find out why is URLWithString: returning nil here.
7 Answers
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Rails Observer Alternatives for 4.0
With Observers officially removed from Rails 4.0 , I'm curious what other developers are using in their place. (Other than using the extracted gem.) While Observers were certainly abused and could easily become unwieldily at times, there were many use-cases outside of just cache-clearing where they...
Origin null is not allowed by Access-Control-Allow-Origin
I have made a small xslt file to create an html output called weather.xsl with code as follows:
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Check if Python Package is installed
What's a good way to check if a package is installed while within a Python script? I know it's easy from the interpreter, but I need to do it within a script.
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What is the easiest way to duplicate an activerecord record?
...y of an activerecord record, changing a single field in the process (in addition to the id ). What is the simplest way to accomplish this?
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You need to use a Theme.AppCompat theme (or descendant) with this activity
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The reason you are having this problem is because the activity you are trying to apply the dialog theme to is extending ActionBarActivity which requires the AppCompat theme to be applied.
Update: Extending AppCompatActivity would also have this problem
In this case, change the ...
How do I directly modify a Google Chrome Extension File? (.CRX)
I'm not sure in which languages those extensions are, I think the are written in Html, Javascript or JSON. As far as I know they are "compressed" in a .CRX file.
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Regular vs Context Free Grammars
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Regular grammar is either right or left linear, whereas context free grammar is basically any combination of terminals and non-terminals. Hence you can see that regular grammar is a subset of context-free grammar.
So for a palindrome for instan...
Set default CRAN mirror permanent in R
...t repos in your .Rprofile to restore your choice every time you start R
Edit: to be more precise:
Add
options(repos=structure(c(CRAN="YOUR FAVORITE MIRROR")))
to your .Rprofile
Alternatively, you can set the mirror site-wide in your Rprofile.site. The location of the file is given by ?Start...