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Get exception description and stack trace which caused an exception, all as a string
...
See the traceback module, specifically the format_exc() function. Here.
import traceback
try:
raise ValueError
except ValueError:
tb = traceback.format_exc()
else:
tb = "No error"
finally:
print tb
...
Inverse dictionary lookup in Python
...o guarantee that it returns a single value and it does not need to be lexically first only that it be the first match and that it's behavior is stable (multiple calls on same dict over time should yield same matching element). Unless dictionaries rearrange their unmodified hashes over time as other...
Alternatives to JavaScript
...ipt is like Java because it has similar syntax and a similar name, but actually it's a lot more like lisp. It's actually pretty well suited to DOM manipulation.
The real problem is that it's compiled by the browser, and that means it works in a very different way depending on the client.
Not only ...
How to darken a background using CSS?
....png);
}
Reference: linear-gradient() - CSS | MDN
UPDATE: Not all browsers support RGBa, so you should have a 'fallback color'. This color will be most likely be solid (fully opaque) ex:background:rgb(96, 96, 96). Refer to this blog for RGBa browser support.
...
Chaining multiple filter() in Django, is this a bug?
I always assumed that chaining multiple filter() calls in Django was always the same as collecting them in a single call.
4...
Why prefer two's complement over sign-and-magnitude for signed numbers?
...o add them.
Two's complement addition is very simple. You add numbers normally and any carry bit at the end is discarded. So they're added as follows:
0010
+ 1111
=10001
= 0001 (discard the carry)
0001 is 1, which is the expected result of "2+(-1)".
But in your "intuitive" method, adding is m...
How many files can I put in a directory?
... subdirectories. Also maximum filesize grew to 16 TB. Furthermore, the overall size of the filesystem may be up to 1 EB = 1,048,576 TB.
– devsnd
Jun 25 '12 at 23:13
7
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Understanding __get__ and __set__ and Python descriptors
...th the Temperature class). For example:
temp=Temperature()
temp.celsius #calls celsius.__get__
Accessing the property you assigned the descriptor to (celsius in the above example) calls the appropriate descriptor method.
instance in __get__ is the instance of the class (so above, __get__ would r...
MySQL DROP all tables, ignoring foreign keys
Is there a nice easy way to drop all tables from a MySQL database, ignoring any foreign key constraints that may be in there?
...
Logical operators for boolean indexing in Pandas
...Error: The truth value of an array is ambiguous. Use a.empty, a.any() or a.all().
when used as a boolean value. That's because its unclear when it should be True or False. Some users might assume they are True if they have non-zero length, like a Python list. Others might desire for it to be True ...