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How can I create a copy of an object in Python?
...would like to create a copy of an object. I want the new object to possess all properties of the old object (values of the fields). But I want to have independent objects. So, if I change values of the fields of the new object, the old object should not be affected by that.
...
What's the difference between using CGFloat and float?
I tend to use CGFloat all over the place, but I wonder if I get a senseless "performance hit" with this. CGFloat seems to be something "heavier" than float, right? At which points should I use CGFloat, and what makes really the difference?
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What's the UIScrollView contentInset property for?
... answered Dec 31 '09 at 1:21
jballjball
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Catching an exception while using a Python 'with' statement
... print 'oops'
If you want different handling for errors from the open call vs the working code you could do:
try:
f = open('foo.txt')
except IOError:
print('error')
else:
with f:
print f.readlines()
...
How is a CRC32 checksum calculated?
... 1 0000 0100 1100 0001 0001 1101 1011 0111
The highest term (x32) is usually not explicitly written, so it can instead be represented in hex just as
0x 04 C1 1D B7
Feel free to count the 1s and 0s, but you'll find they match up with the polynomial, where 1 is bit 0 (or the first bit) and x ...
Combining C++ and C - how does #ifdef __cplusplus work?
...f legacy C code. We've started writing in C++, with the intent to eventually convert the legacy code, as well. I'm a little confused about how the C and C++ interact. I understand that by wrapping the C code with extern "C" the C++ compiler will not mangle the C code's names, but I'm no...
How do I correctly clean up a Python object?
...it close() statement is that you have to worry about people forgetting to call it at all or forgetting to place it in a finally block to prevent a resource leak when an exception occurs.
To use the with statement, create a class with the following methods:
def __enter__(self)
def __exit__(self...
How to find out what type of a Mat object is with Mat::type() in OpenCV
...";
r += (chans+'0');
return r;
}
If M is a var of type Mat you can call it like so:
string ty = type2str( M.type() );
printf("Matrix: %s %dx%d \n", ty.c_str(), M.cols, M.rows );
Will output data such as:
Matrix: 8UC3 640x480
Matrix: 64FC1 3x2
Its worth noting that there are also Matr...
JRE 1.7 - java version - returns: java/lang/NoClassDefFoundError: java/lang/Object
...
This problem stems from an improper Java installation.
Possibility 1
NOTE: This scenario only applies to Java 8 and prior. Beginning with Java 9, the JRE is structured differently. rt.jar and friends no longer exist, and Pack200 is no longer used.
The Java standa...
How do I get the real .height() of a overflow: hidden or overflow: scroll div?
...qual to the minimum clientHeight the element would require in order to fit all the content in the viewpoint without using a vertical scrollbar. It includes the element padding but not its margin.
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