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JavaScript checking for null vs. undefined and difference between == and ===
...is the difference between the null and undefined?
They're both values usually used to indicate the absence of something. undefined is the more generic one, used as the default value of variables until they're assigned some other value, as the value of function arguments that weren't provided when ...
Linear Regression and group by in R
...
fits <- lmList(response ~ year | state, data=d)
fits
#------------
Call: lmList(formula = response ~ year | state, data = d)
Coefficients:
(Intercept) year
CA -1.34420990 0.17139963
NY 0.00196176 -0.01852429
Degrees of freedom: 20 total; 16 residual
Residual standard error: 0.820...
In what areas might the use of F# be more appropriate than C#? [closed]
... sweet spot for the language within enterprise software, namely algorithmically complex analysis of large data sets. My experience has been a very positive one. In particular:
Units of measure The industry I work in is littered with units. The equations I implemented (often of a geometric nature) d...
Manually adding a Userscript to Google Chrome
Instead of "installing" User-Scripts I found many tutorials on the web to add it manually. All of them told me to do the same steps:
...
How to change navbar collapse threshold using Twitter bootstrap-responsive?
... I can't think of any way to achieve the overriding without restating all the CSS declarations.
– methodofaction
Feb 23 '12 at 5:15
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Sorting 1 million 8-decimal-digit numbers with 1 MB of RAM
... the following way:
First take 2 variables: COUNTER and VALUE.
First set all registers to 0;
Every time you receive an integer I, increment COUNTER and set VALUE to max(VALUE, I);
Then send an ICMP echo request packet with data set to I to the router. Erase I and repeat.
Every time you receive the...
Hide grid row in WPF
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UpVoted - Converters permit all this to be declarative in Xaml. I generally hate using code-behind to fiddle with visual stuff.
– Allen
May 22 '14 at 13:43
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Should 'using' directives be inside or outside the namespace?
...
There is actually a (subtle) difference between the two. Imagine you have the following code in File1.cs:
// File1.cs
using System;
namespace Outer.Inner
{
class Foo
{
static void Bar()
{
double d = Ma...
What is the direction of stack growth in most modern systems?
...
Stack growth doesn't usually depend on the operating system itself, but on the processor it's running on. Solaris, for example, runs on x86 and SPARC. Mac OSX (as you mentioned) runs on PPC and x86. Linux runs on everything from my big honkin' Syste...
What's the opposite of 'make install', i.e. how do you uninstall a library in Linux?
...not touch the rest of the filesystem and so will not remove previously installed software.
If you're lucky, running make uninstall will work. It's up to the library's authors to provide that, however; some authors provide an uninstall target, others don't.
If you're not lucky, you'll have to manu...