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What's the difference between lists and tuples?
...tructure, lists have order.
Using this distinction makes code more explicit and understandable.
One example would be pairs of page and line number to reference locations in a book, e.g.:
my_location = (42, 11) # page number, line number
You can then use this as a key in a dictionary to store ...
Local variables in nested functions
Okay, bear with me on this, I know it's going to look horribly convoluted, but please help me understand what's happening.
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Extracting text OpenCV
...v::rectangle(img1,letterBBoxes1[i],cv::Scalar(0,255,0),3,8,0);
cv::imwrite( "imgOut1.jpg", img1);
for(int i=0; i< letterBBoxes2.size(); i++)
cv::rectangle(img2,letterBBoxes2[i],cv::Scalar(0,255,0),3,8,0);
cv::imwrite( "imgOut2.jpg", img2);
return 0;
}
Results:
a. el...
How do I check if I'm running on Windows in Python? [duplicate]
I found the platform module but it says it returns 'Windows' and it's returning 'Microsoft' on my machine. I notice in another thread here on stackoverflow it returns 'Vista' sometimes.
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Google Maps: how to get country, state/province/region, city given a lat/long value?
I need a list of countries, states & cities based on a collection of lat/long values I have. I need to store this information in a manner that hierarchy is preserve and without duplicates (e.g. "USA" and "United States" and "United States of America" are the same country; I only want one instance of...
PHP Fatal error: Cannot redeclare class
...
It means you've already created a class.
For instance:
class Foo {}
// some code here
class Foo {}
That second Foo would throw the error.
share...
Using curl to upload POST data with files
...RL to not only send data parameters in HTTP POST but to also upload files with specific form name. How should I go about doing that ?
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Is it expensive to use try-catch blocks even if an exception is never thrown?
We know that it is expensive to catch exceptions. But, is it also expensive to use a try-catch block in Java even if an exception is never thrown?
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How do I find out which keystore was used to sign an app?
...:E7:E3:0C:AA:7A:0D:F2:0D:05:20:12:A8:85:0B:32:C5:4F:68
Signature algorithm name: SHA1withRSA
Then use the keytool again to print out all the aliases of your signing keystore:
keytool -list -keystore my-signing-key.keystore
You will get a list of aliases and their certificate fingerprint:
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Weak and strong property setter attributes in Objective-C
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You either have ARC on or off for a particular file. If its on you cannot use retain release autorelease etc... Instead you use strong weak for properties or __strong
__weak
for variables (defaults to __strong). Strong is the ...