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How to find the size of an array in postgresql
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112
As vyegorov mentioned, array_length will do the trick. Or if you know that the array is 1-dimen...
How do I delete a fixed number of rows with sorting in PostgreSQL?
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answered Mar 2 '11 at 18:01
community wiki
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How to use a different version of python during NPM install?
I have terminal access to a VPS running centos 5.9 and default python 2.4.3 installed. I also installed python 2.7.3 via these commands: (I used make altinstall instead of make install )
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How do I sort an array of hashes by a value in the hash?
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216
Ruby's sort doesn't sort in-place. (Do you have a Python background, perhaps?)
Ruby has sort! ...
How can I change Eclipse theme?
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126
Take a look at rogerdudler/eclipse-ui-themes . In the readme there is a link to a file that you...
Shading a kernel density plot between two points.
...x,y) pairs.
Edit: Here you go:
x1 <- min(which(dens$x >= q75))
x2 <- max(which(dens$x < q95))
with(dens, polygon(x=c(x[c(x1,x1:x2,x2)]), y= c(0, y[x1:x2], 0), col="gray"))
Output (added by JDL)
share
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What do single quotes do in C++ when used on multiple characters?
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285
It's a multi-character literal. 1952805748 is 0x74657374, which decomposes as
0x74 -> 't'
0...
What's the difference between --general-numeric-sort and --numeric-sort options in gnu sort
... sort compares the numbers as floats, this allows scientific notation eg 1.234E10 but is slower and subject to rounding error (1.2345678 could come after 1.2345679), numeric sort is just a regular alphabetic sort that knows 10 comes after 9.
See http://www.gnu.org/software/coreutils/manual/htm...
Plotting time in Python with Matplotlib
...imestamps to Python datetime objects (use datetime.strptime). Then use date2num to convert the dates to matplotlib format.
Plot the dates and values using plot_date:
dates = matplotlib.dates.date2num(list_of_datetimes)
matplotlib.pyplot.plot_date(dates, values)
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Process all arguments except the first one (in a bash script)
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692
Use this:
echo "${@:2}"
The following syntax:
echo "${*:2}"
would work as well, but is n...