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What does .SD stand for in data.table in R
...mples below, this is particularly helpful for chaining together "queries" (extractions/subsets/etc using [). In particular, this also means that .SD is itself a data.table (with the caveat that it does not allow assignment with :=).
The simpler usage of .SD is for column subsetting (i.e., when .SDc...
Synchronous request in Node.js
... works. I've tried other examples here and was stumped when there was much extra setup to do or installs didn't work!
Notes:
The example that sync-request uses doesn't play nice when you use res.getBody(), all get body does is accept an encoding and convert the response data. Just do res.body.toStri...
Trim a string based on the string length
I want to trim a string if the length exceeds 10 characters.
11 Answers
11
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How can I make my custom objects Parcelable?
...plementation.
public class Student implements Parcelable{
private String id;
private String name;
private String grade;
// Constructor
public Student(String id, String name, String grade){
this.id = id;
this.name = name;
t...
Convert Rows to columns using 'Pivot' in SQL Server
...rate the week number dynamically, your code will be:
DECLARE @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX)
select @cols = STUFF((SELECT ',' + QUOTENAME(Week)
from yt
group by Week
order by Week
FOR XML PATH(''), TYPE
...
convert a list of objects from one type to another using lambda expression
....
List<char> c = new List<char>() { 'A', 'B', 'C' };
List<string> s = c.Select(x => x.ToString()).ToList();
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Objective-C parse hex string to integer
I would like to know how to parse a hex string, representing a number, in Objective-C. I am willing to use both an objective, or a C-based method, either is fine.
...
与复制构造函数相关的错误.例如:0x77D9FCAA (ntdll.dll) (prog31.exe 中)处...
...含指针成员，没有复制构造函数出错
struct Node
{
Node(char *n="",int a = 0)
{
name = strdup(n);
strcpy(name,n);
age = a ;
}
~Node()
{
delete[] name;
}
char *name;
int age;
};
int main()
{
Node node1("Roger",20),node2(node1);
//pri...
Android: Coloring part of a string using TextView.setText()?
...
Use spans.
Example:
final SpannableStringBuilder sb = new SpannableStringBuilder("your text here");
// Span to set text color to some RGB value
final ForegroundColorSpan fcs = new ForegroundColorSpan(Color.rgb(158, 158, 158));
// Span to make text bold
fina...
Using curl POST with variables defined in bash script functions
...i.e. 1:
Simply add ' before and after $variable when replacing desired
string
for i in {1..3}; do \
curl -X POST -H "Content-Type: application/json" -d \
'{"number":"'$i'"}' "https://httpbin.org/post"; \
done
2. For input with spaces:
Wrap variable with additional " i.e. "el a":
decla...