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Heroku free account limited?
...o requests. If each instance of your application can serve each request in 100ms, then you get 600 requests/minute with the free account.
Your application code and its assets (the slug) are limited to 300 MB in total. Your application also has access to the local filesystem, which can serve as an e...
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...
Null coalescing in powershell
...ssignment, and ternary operators in Powershell.
Null Coalescing
$null ?? 100 # Result is 100
"Evaluated" ?? (Expensive-Operation "Not Evaluated") # Right side here is not evaluated
Null Conditional Assignment
$x = $null
$x ??= 100 # $x is now 100
$x ??= 200 # $x remains 100
Terna...
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...
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...
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" ...
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...
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 ...