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How to override a JavaScript function
...nction by just re-declaring it.
parseFloat = function(a){
alert(a)
};
Now parseFloat(3) will alert 3.
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How to split a column into two columns?
...ing the power of the str.extract() method.
But for a simple split over a known separator (like, splitting by dashes, or splitting by whitespace), the .str.split() method is enough1. It operates on a column (Series) of strings, and returns a column (Series) of lists:
>>> import pandas as p...
Best Practice for Exception Handling in a Windows Forms Application?
...ss of writing my first Windows Forms application. I've read a few C# books now so I've got a relatively good understanding of what language features C# has to deal with exceptions. They're all quite theoretical however so what I haven't got yet is a feel for how to translate the basic concepts into ...
How to get the last character of a string in a shell?
...
I know this is a very old thread, but no one mentioned which to me is the cleanest answer:
echo -n $str | tail -c 1
Note the -n is just so the echo doesn't include a newline at the end.
...
What are bitwise operators?
...
Wow, that makes a lot more sense now. It sounded a lot more complicated than it apparently is. Thanks. I'm not sure which to choose as the right answer as there are loads of good ones, and I can't upvote so.. thanks
– click
...
Best way to reverse a string
...
@dok1 - don't mention it :) @sambo99 - now I'm intrigued, will have to whip out a code profiler tomorrow and have a look!
– Greg Beech
Oct 23 '08 at 0:50
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How to properly assert that an exception gets raised in pytest?
...nstantly evolves and with one of the nice changes in the recent past it is now possible to simultaneously test for
the exception type (strict test)
the error message (strict or loose check using a regular expression)
Two examples from the documentation:
with pytest.raises(ValueError, match='mu...
List comprehension on a nested list?
...s actually same as :
New_list=[]
for x in l:
New_list.append(x)
And now nested list comprehension :
[[float(y) for y in x] for x in l]
is same as ;
new_list=[]
for x in l:
sub_list=[]
for y in x:
sub_list.append(float(y))
new_list.append(sub_list)
print(new_list)
o...
How to copy an object in Objective-C
...lways with reference types, there are two notions of "copy". I'm sure you know them, but for completeness.
A bitwise copy. In this, we just copy the memory bit for bit - this is what NSCopyObject does. Nearly always, it's not what you want. Objects have internal state, other objects, etc, and ofte...
Foreign Key to non-primary key
... key, otherwise, data-garbage is the result sooner rather than later...
Now what you can do in this case (short of rewritting the entire application) is inserting a CHECK-constraint, with a scalar function checking the presence of the key:
IF EXISTS (SELECT * FROM sys.check_constraints WHERE ob...