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django models selecting single field

... a good optimization technique, but make sure that you do not create these extra queries. Otherwise you will lose performance instead of gaining it. – Eerik Sven Puudist Jul 19 at 18:47 ...
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How to print the ld(linker) search path

...and: ld --verbose | grep SEARCH_DIR | tr -s ' ;' \\012 gcc passes a few extra -L paths to the linker, which you can list with the following command: gcc -print-search-dirs | sed '/^lib/b 1;d;:1;s,/[^/.][^/]*/\.\./,/,;t 1;s,:[^=]*=,:;,;s,;,; ,g' | tr \; \\012 The answers suggesting to use ld.s...
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Slicing of a NumPy 2d array, or how do I extract an mxm submatrix from an nxn array (n>m)?

I want to slice a NumPy nxn array. I want to extract an arbitrary selection of m rows and columns of that array (i.e. without any pattern in the numbers of rows/columns), making it a new, mxm array. For this example let us say the array is 4x4 and I want to extract a 2x2 array from it. ...
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Convert a python UTC datetime to a local datetime using only python standard library?

...d. Given that dateutil might fail on both Unix and Windows. btw, you could extract utctotimestamp(utc_dt) -> (seconds, microseconds) from your code for clarity, see Python 2.6-3.x implementation – jfs Oct 28 '12 at 20:08 ...
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Why does sun.misc.Unsafe exist, and how can it be used in the real world?

...}, such as {@link java.util.concurrent.atomic.AtomicLongArray}, require extra memory ordering guarantees which are generally not needed in these algorithms and are also expensive on most processors. SoyLatte - java 6 for osx javadoc excerpt /** Base class for sun.misc.Unsafe-based F...
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Line continuation for list comprehensions or generator expressions in python

...t appears at the end of a line, where it either doesn't stand out or needs extra padding, which has to be fixed when line lengths change: x = very_long_term \ + even_longer_term_than_the_previous \ + a_third_term In such cases, use parens: x = (very_long_term + even_...
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Install go with brew, and running the gotour

... I had to put an extra bin/ on the end, since it seems now that they put these go executables into a subdirectory now. I.e., the command for my path is: export PATH=$PATH:/usr/local/Cellar/go/1.3.3/bin/bin/ – Nate ...
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Managing CSS Explosion

... @Miguel, it doesn't work that way. Browsers read a CSS string backwards, so it would take: "div .myclass" and find all ".myclass" classes, and then check if it is an ancestor of a div. – mwilcox Jan 27 '11 at 19:04 ...
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Twig: in_array or similar possible within if statement?

...the accepted answer back in 2012. This answer doesn't seem to add anything extra. – William Isted Aug 18 '16 at 14:43 7 ...
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Why compile Python code?

...ytecode are generally not all that hard to reverse-compile unless you take extra steps to obfuscate them - merely compiling generally won't be sufficient. – EJoshuaS - Reinstate Monica Jul 12 '19 at 13:54 ...