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Python: What OS am I running on?
...consistent output. i.e. platform.system() returns "Windows" instead of "win32". sys.platform also contains "linux2" on old versions of Python while it contains just "linux" on newer ones. platform.system() has always returned just "Linux".
– erb
Jun 9 '17 at 10...
How to see which flags -march=native will activate?
I'm compiling my C++ app using GCC 4.3. Instead of manually selecting the optimization flags I'm using -march=native , which in theory should add all optimization flags applicable to the hardware I'm compiling on. But how can I check which flags is it actually using?
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Python Pandas merge only certain columns
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You can use .loc to select the specific columns with all rows and then pull that. An example is below:
pandas.merge(dataframe1, dataframe2.iloc[:, [0:5]], how='left', on='key')
In this example, you are merging dataframe1 and dataframe2. You have chosen to do an outer left jo...
On delete cascade with doctrine2
...ple in order to learn how to delete a row from a parent table and automatically delete the matching rows in the child table using Doctrine2.
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Force CloudFront distribution/file update
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Good news. Amazon finally added an Invalidation Feature. See the API Reference.
This is a sample request from the API Reference:
POST /2010-08-01/distribution/[distribution ID]/invalidation HTTP/1.0
Host: cloudfront.amazonaws.com
Authorization:...
Why isn't ProjectName-Prefix.pch created automatically in Xcode 6?
Why isn't ProjectName-Prefix.pch created automatically in Xcode 6 ?
8 Answers
8
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Remove duplicates from an array of objects in JavaScript
...) dot notation. Yours is ES5 syntax. The others are mostly ES6 (ECMA2015). All are valid in 2017. See jaredwilli's comment.
– agm1984
Nov 15 '17 at 9:20
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Floating point vs integer calculations on modern hardware
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From my experience, there are many, many variables to performance...especially between integer & floating point math. It varies strongly from processor to processor (even within the same family such as x86) because different processors have different "pipeline" lengths. Also, some operations ...
Error: Jump to case label
...code, if foo equals 1, everything is ok, but if it equals 2, we'll accidentally use the i variable which does exist but probably contains garbage.
switch(foo) {
case 1:
int i = 42; // i exists all the way to the end of the switch
dostuff(i);
break;
case 2:
dostuff(i*2); // i is ...
JavaScript open in a new window, not tab
I have a select box that calls window.open(url) when an item is selected. Firefox will open the page in a new tab by default. However, I would like the page to open in a new window, not a new tab.
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