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How to delete items from a dictionary while iterating over it?
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EDIT:
This answer will not work for Python3 and will give a RuntimeError.
RuntimeError: dictionary changed size during iteration.
This happens because mydict.keys() returns an iterator not a list.
As pointed out in comments simply convert mydict.keys() to a list ...
jQuery and AJAX response header
So I've got this jQuery AJAX call, and the response comes from the server in the form of a 302 redirect. I'd like to take this redirect and load it in an iframe, but when I try to view the header info with a javascript alert, it comes up null, even though firebug sees it correctly.
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How to call shell commands from Ruby
How do I call shell commands from inside of a Ruby program? How do I then get output from these commands back into Ruby?
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Downcasting in Java
... @UnKnown: it shouldn't. Double check that you actually compiled and ran that version and if you can still reproduce it, post a separate question (with an SSCCE).
– Joachim Sauer
Apr 20 '16 at 16:04
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Creating C macro with ## and __LINE__ (token concatenation with positioning macro)
...m is that when you have a macro replacement, the preprocessor will only expand the macros recursively if neither the stringizing operator # nor the token-pasting operator ## are applied to it. So, you have to use some extra layers of indirection, you can use the token-pasting operator with a recurs...
Spring Expression Language (SpEL) with @Value: dollar vs. hash ($ vs. #)
... ${...} . Furthermore, when I started with SpEL I was told to use ${...} and it works fine.
4 Answers
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Remove an entire column from a data.frame in R
...on't need drop argument cause it always return data.frame from data.frame. And I think this is much better way to localized columns (and only columns) in data.frame (and it's faster). Check: cars[-1] (one col data.frame) or better cars[-(1:2)]: data frame with 0 columns and 50 rows.
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How to move files from one git repo to another (not a clone), preserving history
...ory, since you wanted to end up with only a (renamed) subset of the files, and this by definition changes the hashes. Since none of the standard commands (e.g. pull) rewrite history, there's no way you could use them to accomplish this.
You could refine the details, of course - some of your cloning...
How can I view live MySQL queries?
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You can run the MySQL command SHOW FULL PROCESSLIST; to see what queries are being processed at any given time, but that probably won't achieve what you're hoping for.
The best method to get a history without having to modify every application using ...
Cluster analysis in R: determine the optimal number of clusters
..., calinski.best, "\n")
# 5 clusters!
Four. Determine the optimal model and number of clusters according to the Bayesian Information Criterion for expectation-maximization, initialized by hierarchical clustering for parameterized Gaussian mixture models
# See http://www.jstatsoft.org/v18/i06/pap...