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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...
Is there a way to chain multiple value converters in XAML?
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@DLeh This is not really elegant as is doesn't work. It provides all converters with final target type instead of correct target type...
– Aleksandar Toplek
Sep 7 '15 at 10:53
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Default template arguments for function templates
Why are default template arguments only allowed on class templates? Why can't we define a default type in a member function template? For example:
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System.Threading.Timer in C# it seems to be not working. It runs very fast every 3 second
I've a timer object. I want it to be run every minute. Specifically, it should run a OnCallBack method and gets inactive while a OnCallBack method is running. Once a OnCallBack method finishes, it (a OnCallBack ) restarts a timer.
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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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Mongodb Explain for Aggregation framework
...ther manipulation will be in-memory (possibly using temporary files if the allowDiskUse option is set).
Optimizing pipelines
In general, you can optimize aggregation pipelines by:
Starting a pipeline with a $match stage to restrict processing to relevant documents.
Ensuring the initial $match / ...
How to find out if an installed Eclipse is 32 or 64 bit version?
...e the line with text:
plugins/org.eclipse.equinox.launcher.win32.win32.x86_64_1.0.200.v20090519
then it is 64 bit.
If it would be plugins/org.eclipse.equinox.launcher.win32.win32.x86_32_1.0.200.v20090519 then it is 32 bit.
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Conditional HTML Attributes using Razor MVC3
...s" />
If strCSSClass is null then the class attribute won't render at all.
SSSHHH...don't tell. :)
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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 ...