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What's the difference between `1L` and `1`?
...re adding 1 to an integer vector turns it into a double vector:
x <- 1:100
typeof(x) # integer
y <- x+1
typeof(y) # double, twice the memory size
object.size(y) # 840 bytes (on win64)
z <- x+1L
typeof(z) # still integer
object.size(z) # 440 bytes (on win64)
...but also note that work...
How to force R to use a specified factor level as reference in a regression?
...e the relevel() function. Here is an example:
set.seed(123)
x <- rnorm(100)
DF <- data.frame(x = x,
y = 4 + (1.5*x) + rnorm(100, sd = 2),
b = gl(5, 20))
head(DF)
str(DF)
m1 <- lm(y ~ x + b, data = DF)
summary(m1)
Now alter the factor b in DF by use of t...
Select SQL Server database size
... MB
Function:
ALTER FUNCTION [dbo].[GetDBSize]
(
@db_name NVARCHAR(100)
)
RETURNS TABLE
AS
RETURN
SELECT
database_name = DB_NAME(database_id)
, log_size_mb = CAST(SUM(CASE WHEN type_desc = 'LOG' THEN size END) * 8. / 1024 AS DECIMAL(8,2))
, row_size_mb = CAST(SUM(CASE...
How would you make two s overlap?
...dth: 300px;
height: 200px;
z-index: 2;
}
#content {
margin-top: 100px; /* Provide buffer for logo */
}
#links {
height: 75px;
margin-left: 400px; /* Flush links (with a 25px "padding") right of logo */
}
<div id="logo">
<img src="https://via.placeholder.com/200x100" ...
File upload progress bar with jQuery
...t.loaded / evt.total;
percentComplete = parseInt(percentComplete * 100);
console.log(percentComplete);
if (percentComplete === 100) {
}
}
}, false);
return xhr;
},
url: posturlfile,
type: "POST",
data: JSON.stringify(fileuploaddata),
conten...
Replacing NAs with latest non-NA value
...,'a',NA,NA,NA,NA,NA,NA,NA,NA,'b','c','d',NA,NA,NA,NA,NA,'e')
xx = rep(x, 1000000)
system.time({ yzoo = na.locf(xx,na.rm=F)})
## user system elapsed
## 2.754 0.667 3.406
system.time({ yrep = repeat.before(xx)})
## user system elapsed
## 0.597 0.199 0.793
Edit
As this ...
Export database schema into SQL file
...DENTITY(1,1)
,DatabaseName VARCHAR(100)
,TableOwner VARCHAR(100)
,TableName VARCHAR(100)
,FieldName VARCHAR(100)
...
Changing specific text's color using NSMutableAttributedString in Swift
...ange: range)
textField = UITextField.init(frame: CGRect(x:10, y:20, width:100, height: 100))
textField.attributedText = mutableAttributedString
SWIFT 4.2
let range = (mainString as NSString).range(of: stringToColor)
let mutableAttributedString = NSMutableAttributedString.init(string: mainStr...
What is the best way to get all the divisors of a number?
...
wow it took 0.01 for calculating all divisors of 100000000 against the 39s that took the dumb way (stopping at n/2) very cool, thank you!
– Andrea Ambu
Oct 5 '08 at 10:20
...
Which is the preferred way to concatenate a string in Python?
...(b):
0.010656118392944336
The end string, therefore, ends up being about 100MB long. That was pretty slow, appending to a list was much faster. That that timing doesn't include the final a.join(). So how long would that take?
a.join(a):
0.43739795684814453
Oups. Turns out even in this case, ap...