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Explicitly select items from a list or tuple
...ilt-in, but you can make a subclass of list that takes tuples as "indexes" if you'd like:
class MyList(list):
def __getitem__(self, index):
if isinstance(index, tuple):
return [self[i] for i in index]
return super(MyList, self).__getitem__(index)
seq = MyList("foo...
Remove an entire column from a data.frame in R
...ne know how to remove an entire column from a data.frame in R? For example if I am given this data.frame:
6 Answers
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How to parse a CSV file in Bash?
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You need to use IFS instead of -d:
while IFS=, read -r col1 col2
do
echo "I got:$col1|$col2"
done < myfile.csv
Note that for general purpose CSV parsing you should use a specialized tool which can handle quoted fields with internal...
UIActivityViewController crashing on iOS 8 iPads
...er using the new UIPopoverPresentationController, it requires that you specify an anchor point for the presentation of the popover using one of the three following properties:
barButtonItem
sourceView
sourceRect
In order to specify the anchor point you will need to obtain a reference to the UIAc...
Media Queries - In between two widths
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@Jonathan Sampson i think your solution is wrong if you use multiple @media.
You should use (min-width first):
@media screen and (min-width:400px) and (max-width:900px){
...
}
share
|...
Can you require two form fields to match with HTML5?
...ng HTML5? Or does this still have to be done with javascript? For example, if you have two password fields and want to make sure that a user has entered the same data in each field, are there some attributes, or other coding that can be done, to achieve this?
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In log4j, does checking isDebugEnabled before logging improve performance?
...re up-to-date logging framework where the log statements take a format specification and a list of arguments to be substituted by the logger—but "lazily," only if the logger is enabled. This is the approach taken by slf4j.
See my answer to a related question for more information, and an example o...
Cycles in family tree software
...tal misunderstanding of what a family tree is supposed to be.
Let me clarify, I also work for a company that has (as one of its products) a family tree in its portfolio, and we have been struggling with similar problems.
The problem, in our case, and I assume your case as well, comes from the GED...
Get a list of checked checkboxes in a div using jQuery
...w Do i get only the count of the selected checkboxes? I just need to check if any of the checkboxes inside the div is checked or not.
– ashishjmeshram
May 9 '12 at 4:05
1
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How do I restore a dump file from mysqldump?
...s simple as running this:
mysql -u <user> -p < db_backup.dump
If the dump is of a single database you may have to add a line at the top of the file:
USE <database-name-here>;
If it was a dump of many databases, the use statements are already in there.
To run these commands, op...