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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...
Calculating frames per second in a game
...
100
You need a smoothed average, the easiest way is to take the current answer (the time to draw t...
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...
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...
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...
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" ...
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 ...
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...
Export database schema into SQL file
...DENTITY(1,1)
,DatabaseName VARCHAR(100)
,TableOwner VARCHAR(100)
,TableName VARCHAR(100)
,FieldName VARCHAR(100)
...
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
...