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Dynamically select data frame columns using $ and a character value
...is a reproducible example below:
# set seed for reproducibility
set.seed(123)
df <- data.frame( col1 = sample(5,10,repl=T) , col2 = sample(5,10,repl=T) , col3 = sample(5,10,repl=T) )
# We want to sort by 'col3' then by 'col1'
sort_list <- c("col3","col1")
# Use 'do.call' to call order. S...
Converting String to Int with Swift
...
swift 4.0
let stringNumber = "123"
let number = Int(stringNumber) //here number is of type "Int?"
//using Forced Unwrapping
if number != nil {
//string is converted to Int
}
you could also use Optional Binding other than forced binding.
eg...
No module named pkg_resources
...
July 2018 Update
Most people should now use pip install setuptools (possibly with sudo).
Some may need to (re)install the python-setuptools package via their package manager (apt-get install, yum install, etc.).
This issue can be highly depe...
How to compare two floating point numbers in Bash?
...result back to the shell in a proper, machine-readable way. if awk -v n1="123.456" -v n2="3.14159e17" 'BEGIN { exit (n1 <= n2) }' /dev/null; then echo bigger; else echo not; fi ... though note how the condition is inverted (the exit status 0 means success to the shell).
– t...
How to recursively find the latest modified file in a directory?
...ntf is probably GNU-only, ajreals usage of stat -c is too. Although it is possible to do the same on BSD, the options for formatting is different (-f "%m %N" it would seem)
And I missed the part of plural; if you want more then the latest file, just bump up the tail argument.
...
ASP.NET Identity reset password
...();//"<YourLogicAssignsRequestedUserId>";
String newPassword = "test@123"; //"<PasswordAsTypedByUser>";
String hashedNewPassword = UserManager.PasswordHasher.HashPassword(newPassword);
ApplicationUser cUser = await store.FindByIdAsync(userId);
await store.SetPasswordH...
How to list all installed packages and their versions in Python?
... :
In [1]: import #import press-TAB
Display all 631 possibilities? (y or n)
ANSI audiodev markupbase
AptUrl audioop markupsafe
ArgImagePlugin avahi marshal
BaseHTTPServer axi ...
Convert a number range to another range, maintaining ratio
...edited Dec 16 '14 at 5:02
Rizier123
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answered Dec 16 '14 at 4:40
...
rmagick gem install “Can't find Magick-config”
...ll with:
$ sudo apt-get install libmagickwand-dev imagemagick
or on centOs:
$ yum install ImageMagick-devel
On Mac OS, you can use Homebrew:
$ brew install imagemagick
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Disabled form inputs do not appear in the request
...;form action="/Media/Add">
<input type="hidden" name="Id" value="123" />
<input type="textbox" name="Percentage" value="100" readonly/>
</form>
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