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Any way to delete in vim without overwriting your last yank? [duplicate]
...in the registers:
"_dd
See also :help registers.
It's probably safest, if you want to paste something over and over again, to yank it into a "named" register.
"aY
Yanks a line into the a register. Paste it with "ap.
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django admin - add custom form fields that are not part of the model
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If for some reason, you get an AttributeError: Unable to lookup "extra_field"..., try adding a label to the extra_field definition. It seems that django tries to "guess" the label for it, by looking at the Model and the Model...
Check that an email address is valid on iOS [duplicate]
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return [emailTest evaluateWithObject:self];
}
@end
And then utilize:
if([@"emailString@email.com" isValidEmail]) { /* True */ }
if([@"InvalidEmail@notreallyemailbecausenosuffix" isValidEmail]) { /* False */ }
share
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Matplotlib: “Unknown projection '3d'” error
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First off, I think mplot3D worked a bit differently in matplotlib version 0.99 than it does in the current version of matplotlib.
Which version are you using? (Try running: python -c 'import matplotlib; print matplotlib."__version__")
I'm guessing you're running v...
How to encrypt/decrypt data in php?
...= openssl_random_pseudo_bytes($key_size, $strong);
// $strong will be true if the key is crypto safe
This can be done once or multiple times (if you wish to create a chain of encryption keys). Keep these as private as possible.
IV
The initialisation vector adds randomness to the encryption and r...
Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
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See the C FAQ, Question 1.32
Q: What is the difference between these initializations?
char a[] = "string literal";
char *p = "string literal";
My program crashes if I try to assign a new value to p[i].
A: A string literal (the formal term
for a double-quot...
How can I convert an RGB image into grayscale in Python?
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knowing that my aim is to use GLCM features (greycoprops)
– Sam
Dec 1 '15 at 20:56
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How to implement the Android ActionBar back button?
...ress the back button. This should be done in the AndroidManifest.xml too.
Now you can enable the back button in the onCreate method of your "child" activity.
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getActionBar().setDisplayHomeAsUp...
C++ convert hex string to signed integer
...dard, there are a few new utility functions which you can make use of! specifically, there is a family of "string to number" functions (http://en.cppreference.com/w/cpp/string/basic_string/stol and http://en.cppreference.com/w/cpp/string/basic_string/stoul). These are essentially thin wrappers aroun...
Insert HTML with React Variable Statements (JSX)
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How does this work if you need to add something to <head>?
– Danielle Madeley
Oct 30 '15 at 3:37
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