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How to read data when some numbers contain commas as thousand separator?
...thod using the setAs function like so:
setClass("num.with.commas")
setAs("character", "num.with.commas",
function(from) as.numeric(gsub(",", "", from) ) )
Then run read.csv like:
DF <- read.csv('your.file.here',
colClasses=c('num.with.commas','factor','character','numeric','num.w...
What's the magic of “-” (a dash) in command-line parameters?
.../home | aescrypt -e -p apples -o backup_files.tar.aes - because the piping char | should make the presence of the last dash unnecessary. But without the last dash the command fails. Sounds illogical. Can someone please give me a reference where the naked dash meaning in command lines is explained. I...
[since C++11] std::array的使用 - C/C++ - 清泛网 - 专注C/C++及内核技术
...-------------------
RUN_GTEST(ArrayTest, CStyleArray, @);
// use array<char> as a fix sized c-string.
array<char, 100> str = {0}; // all elements initialized with 0.
char *p = str.data();
strcpy(p, "hello world");
printf("%s\n", p); // hello world
END_TEST;
上...
How to select unique records by SQL
When I perform "SELECT * FROM table" I got results like below:
8 Answers
8
...
A complete solution to LOCALLY validate an in-app receipts and bundle receipts on iOS 7
...m RMAppReceipt:
+ (NSData*)dataFromPKCS7Path:(NSString*)path
{
const char *cpath = [[path stringByStandardizingPath] fileSystemRepresentation];
FILE *fp = fopen(cpath, "rb");
if (!fp) return nil;
PKCS7 *p7 = d2i_PKCS7_fp(fp, NULL);
fclose(fp);
if (!p7) return nil;
NS...
When should I use cross apply over inner join?
...APPLY works better on things that have no simple JOIN condition.
This one selects 3 last records from t2 for each record from t1:
SELECT t1.*, t2o.*
FROM t1
CROSS APPLY
(
SELECT TOP 3 *
FROM t2
WHERE t2.t1_id = t1.id
ORDER BY
t2.ran...
What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
...
Is there a splice method for strings?
...y case im working on a dynamic string so i need to specify indices and not character value .
– ProllyGeek
Dec 28 '13 at 18:11
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How to add reference to a method parameter in javadoc?
...ass:
/**
* Allocates a new <code>String</code> that contains characters from
* a subarray of the character array argument. The <code>offset</code>
* argument is the index of the first character of the subarray and
* the <code>count</code> argument specifies t...
Capture characters from standard input without waiting for enter to be pressed
...up so infrequently for me. But in C or C++, what is the best way to read a character from standard input without waiting for a newline (press enter).
...