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Storing time-series data, relational or non?
...s to the disk space used.
You can get rid of it. Please.
Elevation
Now that you have removed the impediment, you may not have recognised it, but your table is in Sixth Normal Form. Very high speed, with just one Index on the PK. For understanding, read this answer from the What is Sixth Nor...
How do I add a library project to Android Studio?
... dependency. It won’t mess in your project structure. Almost every well-known Android library is available in a Maven repository and its installation takes only one line of code in the app/build.gradle file:
dependencies {
compile 'com.jakewharton:butterknife:6.0.0'
}
Adding the library
H...
Running shell command and capturing the output
...ompared to the old way of doing things. But I think it's worth the payoff: now you can do almost anything you need to do with the run function alone.
Older versions of Python (2.7-3.4): check_output
If you are using an older version of Python, or need modest backwards compatibility, you can probab...
Assert a function/method was not called using Mock
...led attribute, but if your assertion fails, the next thing you'll want to know is something about the unexpected call, so you may as well arrange for that information to be displayed from the start. Using unittest, you can check the contents of call_args_list instead:
self.assertItemsEqual(my_var.c...
Bootstrap dropdown sub menu missing
...Mark Otto..
"Submenus just don't have much of a place on the web right now, especially the mobile web. They will be removed with 3.0" - https://github.com/twbs/bootstrap/pull/6342
But, with a little extra CSS you can get the same functionality.
Bootstrap 4 (navbar submenu on hover)
.navbar-n...
Create RegExps on the fly using string variables
...
Note also that when you use a RegExp in replace(), the replacement string now has a special character too, $. This must also be escaped if you want to have a literal $ in your replacement text!
function escapeSubstitute(s) {
return s.replace(/\$/g, '$$$$');
}
(Four $s because that is itself ...
How to un-commit last un-pushed git commit without losing the changes
...t those changes are still visible in the history)
git push origin master
now if you want to have those changes as you local changes in your working copy ("so that your local copy keeps the changes made in that commit") - just revert the revert commit with --no-commit option:
git revert --no-commi...
Should you ever use protected member variables?
...
The general feeling nowadays is that they cause undue coupling between derived classes and their bases.
They have no particular advantage over protected methods/properties (once upon a time they might have a slight performance advantage), and t...
Do any JVM's JIT compilers generate code that uses vectorized floating point instructions?
...
So, basically, you want your code to run faster. JNI is the answer. I know you said it didn't work for you, but let me show you that you are wrong.
Here's Dot.java:
import java.nio.FloatBuffer;
import org.bytedeco.javacpp.*;
import org.bytedeco.javacpp.annotation.*;
@Platform(include = "Dot.h...
PHP memory profiling
...
im trying to use qcachegrind now and don't understand what I'm looking at. I don't see memory numbers anywhere. How much memory does each variable take up? I want something that can trace the execution and show the memory at each point, and what varia...