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Should I use a data.frame or a matrix?
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Something not mentioned by @Michal is that not only is a matrix smaller than the equivalent data frame, using matrices can make your code far more efficient than using data frames, often considerably so. That is one reason why internally, a lot of R functions will coerce to matrices data th...
HTML table headers always visible at top of window when viewing a large table
...n if its just a question about how to get it working. Ill respond there usually in under a day. Here ill probably respond in just under a year :)
– mkoryak
Oct 4 '16 at 18:21
1
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How do I return multiple values from a function in C?
...ts own memory.
You have two solutions:
1: Return a struct which contains all the types you need.
struct Tuple {
int a;
string b;
};
struct Tuple getPair() {
Tuple r = { 1, getString() };
return r;
}
void foo() {
struct Tuple t = getPair();
}
2: Use pointers to pass out val...
MongoDB vs. Cassandra [closed]
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Totally different, a comment isn't big enough, but ... Cassandra is a linearly scalable (amortized constant time reads & writes) dynamo/google bigtable hybrid that features fast writes regardless of data size. It's feature s...
Display date/time in user's locale format and time offset
...Also, this whole block could probably be made into an mktime function.
// All very bare here for quick grasping.
d = new Date();
d.setUTCFullYear(2004);
d.setUTCMonth(1);
d.setUTCDate(29);
d.setUTCHours(2);
d.setUTCMinutes(45);
d.setUTCSeconds(26);
console.log(d); /...
CSS selector for first element with class
...lass. One workaround that Lea Verou and I came up with for this (albeit totally independently) is to first apply your desired styles to all your elements with that class:
/*
* Select all .red children of .home, including the first one,
* and give them a border.
*/
.home > .red {
border: ...
Create a new object from type parameter in generic class
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Because the compiled JavaScript has all the type information erased, you can't use T to new up an object.
You can do this in a non-generic way by passing the type into the constructor.
class TestOne {
hi() {
alert('Hi');
}
}
class TestTwo {
...
Options, Settings, Properties, Configuration, Preferences — when and why?
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Tricky, this, as there's no one single consistent style followed by all applications. As you say they are (broadly) synonyms.
In truth it doesn't really matter so long as your expected audience understands what you mean.
The biggest difference is between Properties, which usually affect a c...
What is the best way to test for an empty string in Go?
... one that makes the code clear.
If I'm about to look at element x I typically write
len(s) > x, even for x == 0, but if I care about
"is it this specific string" I tend to write s == "".
It's reasonable to assume that a mature compiler will compile
len(s) == 0 and s == "" into the ...
How to drop columns by name in a data frame
I have a large data set and I would like to read specific columns or drop all the others.
11 Answers
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