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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...
How to install psycopg2 with “pip” on Python?
...s. Below are solutions for Linux, Mac users, since lots of them find this post through web searches.
Option 1
Install the psycopg2-binary PyPI package instead, it has Python wheels for Linux and Mac OS.
pip install psycopg2-binary
Option 2
Install the prerequsisites for building the psycop...
How do I determine if my python shell is executing in 32bit or 64bit?
...tunately, its results are not always reliable, particularly in the case of OS X universal binaries.
$ arch -x86_64 /usr/bin/python2.6 -c 'import sys,platform; print platform.architecture()[0], sys.maxsize > 2**32'
64bit True
$ arch -i386 /usr/bin/python2.6 -c 'import sys,platform; print platform...
Android and in TextView
is it possible to add &nbsp; in TextView? Has anyone achieved similar functionality?
7 Answers
...
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 set environment variables in Jenkins?
...step and set "Properties File Path" to propsfile.
Note: This plugin is (mostly) not compatible with the Pipeline plugin.
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Kill a Process by Looking up the Port being used by it from a .BAT
... /PID %%P
Note that you might need to change this slightly for different OS's. For example, on Windows 7 you might need tokens=5 instead of tokens=4.
How this works
FOR /F ... %variable IN ('command') DO otherCommand %variable...
This lets you execute command, and loop over its output. Each ...
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 do I create a Bash alias?
I'm on OSX and I need to put something like this, alias blah="/usr/bin/blah" in a config file but I don't know where the config file is.
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