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R: rJava package install failing
When installing rJava using the install.packages("rJava") command I get the following error:
16 Answers
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What does “%” (percent) do in PowerShell?
..." symbol - it makes it harder for folks to read/maintain your code - especially people new to PS. Let's face it, the more people that pick up PS, the better.
– Simon Catlin
Apr 3 '14 at 20:17
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How to make a JSONP request from Javascript without JQuery?
...cument.createElement('script');
script.src = '//example.com/path/to/jsonp?callback=foo'
document.getElementsByTagName('head')[0].appendChild(script);
// or document.head.appendChild(script) in modern browsers
share
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Array.push() if does not exist?
... it doesn't then just push the item into the array:
var newItem = "NEW_ITEM_TO_ARRAY";
var array = ["OLD_ITEM_1", "OLD_ITEM_2"];
array.indexOf(newItem) === -1 ? array.push(newItem) : console.log("This item already exists");
console.log(array)
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How can I create tests in Android Studio?
...ow testing works. If you follow along for the next 10 minutes, you will be all set up to start adding your tests to your own app. I think you'll be surprised how easy it is. I certainly was.
Intro to Android Testing
There are two different types of tests that you will do.
Local unit tests. These ar...
How to change value of object which is inside an array using JavaScript or jQuery?
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@FrederikoCesar not in all cases, iterating over each object costs more than slicing the array and inject the new object using spread operator
– Maged Mohamed
Feb 29 at 21:33
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How to delete a word and go into insert mode in Vim?
...aw deletes the trailing space as well.
– Roberto Bonvallet
Sep 7 '09 at 4:38
5
:help objects in v...
How to convert a byte array to a hex string in Java?
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From the discussion here, and especially this answer, this is the function I currently use:
private static final char[] HEX_ARRAY = "0123456789ABCDEF".toCharArray();
public static String bytesToHex(byte[] bytes) {
char[] hexChars = new char[bytes.length * 2...
How can I get the Typescript compiler to output the compiled js to a different directory?
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Though these answers are correct you should consider whether you actually just want to hide your .js files from your IDE.
In Visual Studio Code, go to File > Preferences > Settings or your .vscode\settings.json file and enter:
"files.exclude": {
"**/.git": true,
"**/.DS_Store"...
Read only the first line of a file?
...od (Python 2 docs, Python 3 docs):
with open('myfile.txt') as f:
first_line = f.readline()
Some notes:
As noted in the docs, unless it is the only line in the file, the string returned from f.readline() will contain a trailing newline. You may wish to use f.readline().strip() instead to rem...