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Storing time-series data, relational or non?
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Definitely Relational. Unlimited flexibility and expansion.
Two corrections, both in concept and application, followed by an elevation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Ind...
Attach IntelliJ IDEA debugger to a running Java process
...If you're not sure which of the three applies to you, start with the first and go down the list until you find the one that works.
You can change suspend=n to suspend=y to force your application to wait until you connect with IntelliJ before it starts up. This is helpful if the breakpoint you want ...
How do I change the formatting of numbers on an axis with ggplot?
I'm using R and ggplot to draw a scatterplot of some data, all is fine except that the numbers on the y-axis are coming out with computer style exponent formatting, i.e. 4e+05, 5e+05, etc. This is obviously unacceptable, so I want to get it to display them as 500,000, 400,000, and so on. Getting a p...
Inline SVG in CSS
...rk nicely is Safari (5.1.4). In Opera 11.62 the gradient is black, in IE 9 and Firefox 12 it's white. In Chrome 19, it works UNLESS you specify the width/height of the SVG in % units. I'd say it's more of an oddity than a real feature. It's a cool find though.
– toniedzwiedz
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Specifying and saving a figure with exact size in pixels
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Matplotlib doesn't work with pixels directly, but rather physical sizes and DPI. If you want to display a figure with a certain pixel size, you need to know the DPI of your monitor. For example this link will detect that for you.
If you have an image of 3841x7195 pixels it is unlikely that you m...
What is a message pump?
...ng Office in an interactive session on a desktop, with a monitor, keyboard and mouse and, most importantly, a message pump." I'm not sure what that is. (I've been programming in C# for only about a year; my other programming experience has primarily been with ColdFusion.)
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Does Python support multithreading? Can it speed up execution time?
...n threads in parallel.
This only applies to Python code. C extensions can and do release the GIL to allow multiple threads of C code and one Python thread to run across multiple cores. This extends to I/O controlled by the kernel, such as select() calls for socket reads and writes, making Python ha...
How to delete images from a private docker registry?
I run a private docker registry, and I want to delete all images but the latest from a repository. I don't want to delete the entire repository, just some of the images inside it. The API docs don't mention a way to do this, but surely it's possible?
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Appropriate datatype for holding percent values?
...hat ensures that the values never exceed 1.0000 (assuming that is the cap) and never go below 0 (assuming that is the floor). If you are going to store their face value (e.g. 100.00% is stored as 100.00), then you should use decimal(5,2) with an appropriate CHECK constraint. Combined with a good col...
What is the difference between packaged_task and async
...nces if you use a rather long function, such as
//! sleeps for one second and returns 1
auto sleep = [](){
std::this_thread::sleep_for(std::chrono::seconds(1));
return 1;
};
Packaged task
A packaged_task won't start on it's own, you have to invoke it:
std::packaged_task<int()> tas...