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How do I concatenate or merge arrays in Swift?
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12 Answers
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“ValueError: zero length field name in format” error in Python 3.0,3.1,3.2
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I'm gonna guess that you are running python 2.6 by accident somehow.
This feature is only available for at least 3.1 if you are using python 3, or 2.7 if you are using python 2.
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What is the ideal data type to use when storing latitude / longitude in a MySQL database?
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21 Answers
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Convert a float64 to an int in Go
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213
package main
import "fmt"
func main() {
var x float64 = 5.7
var y int = int(x)
fmt.Print...
Reduce, fold or scan (Left/Right)?
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372
In general, all 6 fold functions apply a binary operator to each element of a collection. The re...
How do I list all versions of a gem available at a remote site?
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Well, it was easier than I thought (well, not really, let's say as easy as it should be):
gem...
Scala: Nil vs List()
...intln (Nil equals List())
true
scala> System.identityHashCode(Nil)
374527572
scala> System.identityHashCode(List())
374527572
Nil is more idiomatic and can be preferred in most cases.
Questions?
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Select first 4 rows of a data.frame in R
...et the rows 5 to 7?
– Bustergun
May 21 '18 at 9:38
You can use the "index" answer pointed out elsewhere. In this situa...
Should I use a data.frame or a matrix?
...e the choice.
Also:
Matrices are more memory efficient:
m = matrix(1:4, 2, 2)
d = as.data.frame(m)
object.size(m)
# 216 bytes
object.size(d)
# 792 bytes
Matrices are a necessity if you plan to do any linear algebra-type of operations.
Data frames are more convenient if you frequently refer to ...
How can you sort an array without mutating the original array?
...);
the spread-syntax as array literal (copied from mdn):
var arr = [1, 2, 3];
var arr2 = [...arr]; // like arr.slice()
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_operator
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