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Getting the count of unique values in a column in bash
...t count first). How would I accomplish this in a Linux command line environm>me m>nt?
5 Answers
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Passing argum>me m>nts with spaces between (bash) script
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$*, unquoted, expands to two words. You need to quote it so that som>me m>App receives a single argum>me m>nt.
som>me m>App "$*"
It's possible that you want to use $@ instead, so that som>me m>App would receive two argum>me m>nts if you were to call b.sh as
b.sh 'My first' 'My second'
With som>me m>App "$*", som>me m>Ap...
Matplotlib: “Unknown projection '3d'” error
...ion 0.99, try doing this instead of using using the projection keyword argum>me m>nt:
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import axes3d, Axes3D #<-- Note the capitalization!
fig = plt.figure()
ax = Axes3D(fig) #<-- Note the difference from your original code...
X, Y, Z = a...
Do you need to use path.join in node.js?
...ath to a Windows command run as a subprocess. Also, Windows API calls (and m>me m>thods from higher-level languages that call the Windows API) that return paths will use backslashes, so even if you aren't passing them to subprocesses, you'll need to normalize them.
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Git: How to rebase to a specific commit?
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You can avoid using the --onto param>me m>ter by making a temp branch on the commit you like and then use rebase in its simple form:
git branch temp master^
git checkout topic
git rebase temp
git branch -d temp
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Postgres dump of only parts of tables for a dev snapshot
On production our database is a few hundred gigabytes in size. For developm>me m>nt and testing, we need to create snapshots of this database that are functionally equivalent, but which are only 10 or 20 gigs in size.
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Chrom>me m> ignores autocomplete=“off”
...which uses a tagbox drop down. This works great in all browsers except Chrom>me m> browser (Version 21.0.1180.89).
51 Answers
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Why is Scala's immutable Set not covariant in its type?
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Set is invariant in its type param>me m>ter because of the concept behind sets as functions. The following signatures should clarify things slightly:
trait Set[A] extends (A=>Boolean) {
def apply(e: A): Boolean
}
If Set were covariant in A, the apply m>me m>t...
What's the point of g++ -Wreorder?
...Wreorder. What this option does is described below. It is not obvious to m>me m> why som>me m>body would care (especially enough to turn this on by default in -Wall).
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in_array multiple values
...at you only need to verify the size of the resulting intersection is the sam>me m> size as the array of target values to say that $haystack is a superset of $target.
To verify that at least one value in $target is also in $haystack, you can do this check:
if(count(array_intersect($haystack, $target)) ...