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What are the differences between numpy arrays and matrices? Which one should I use?
...nces between matrix objects and ndarrays
(having to do with np.ravel, item selection and sequence behavior).
The main advantage of numpy arrays is that they are more general than
2-dimensional matrices. What happens when you want a 3-dimensional array? Then
you have to use an ndarray, not a matrix ...
How does “cat
...1. Assign multi-line string to a shell variable
$ sql=$(cat <<EOF
SELECT foo, bar FROM db
WHERE foo='baz'
EOF
)
The $sql variable now holds the new-line characters too. You can verify with echo -e "$sql".
2. Pass multi-line string to a file in Bash
$ cat <<EOF > print.sh
#!/bin...
Why does Oracle 9i treat an empty string as NULL?
...
@sehe the confusing bit for me is select 1 from dual where ('' is null)
– matt freake
Aug 22 '13 at 15:58
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What is the “volatile” keyword used for?
...latestness" - inherently fake since a lock just force cores to arbitrarily select one speaker at a time w/o fairness - but rather try to design away the need for such an unnatural concept.
– AnorZaken
May 5 at 15:57
...
How to uninstall a Windows Service when there is no executable for it left on the system?
...urite way of doing this is to use Sysinternals Autoruns application. Just select the service and press delete.
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How to randomize (or permute) a dataframe rowwise and columnwise?
...ple(1:n()))
or
df2 <- sample_frac(df1, 1L)
column-wise:
df2 <- select(df1, one_of(sample(names(df1))))
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Rounded table corners CSS only
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The selected answer is terrible. I would implement this by targeting the corner table cells and applying the corresponding border radius.
To get the top corners, set the border radius on the first and last of type of the th ele...
How to allow only numeric (0-9) in HTML inputbox using jQuery?
...n(inputFilter) {
return this.on("input keydown keyup mousedown mouseup select contextmenu drop", function() {
if (inputFilter(this.value)) {
this.oldValue = this.value;
this.oldSelectionStart = this.selectionStart;
this.oldSelectionEnd = this.selectionEnd;
} e...
The smallest difference between 2 Angles
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a one line simple solution and solved for me(not the selected answer ;) ). but tan inverse is a costly process.
– Mohan Kumar
Jun 20 '16 at 16:32
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Creating JSON on the fly with JObject
...item =
from p in posts
orderby p.Title
select new
{
title = p.Title,
description = p.Description,
link = p.Link,
category = p.Categories
}
}
});
Json.net documentation fo...