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Applying a function to every row of a table using dplyr?
...it reflects the fact that when you're doing row wise operations you're actually working with tuples from a list of vectors (the columns in a dataframe).
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How do I use Java to read from a file that is actively being written to?
...verflow.com/a/559146/1255493
public void run() {
try {
while (_running) {
Thread.sleep(_updateInterval);
long len = _file.length();
if (len < _filePointer) {
// Log must have been jibbled or deleted.
this.appendMessa...
How to get the Full file path from URI
...se in oreo we will not get the id but the entire path in data.getData() so all u need to do is create a file from uri and get its path from getPath() and split it.below is the working code:-
Uri uri = data.getData();
File file = new File(uri.getPath());//create path from uri
final String[] split =...
Random “Element is no longer attached to the DOM” StaleElementReferenceException
...r valid. It's close to impossible for WebDriver to make a good guess about all the cases where this might happen - so it throws up its hands and gives control to you, who as the test/app author should know exactly what may or may not happen. What you want to do is explicitly wait until the DOM is in...
OpenCV C++/Obj-C: Detecting a sheet of paper / Square Detection
...e I was unable to find a relevant implementation I decided to accept the challenge.
I made some modifications to the squares demo present in OpenCV and the resulting C++ code below is able to detect a sheet of paper in the image:
void find_squares(Mat& image, vector<vector<Point> >...
Get all directories within directory nodejs
...
Here's a shorter, syncronous version of this answer that can list all directories (hidden or not) in the current directory:
const { lstatSync, readdirSync } = require('fs')
const { join } = require('path')
const isDirectory = source => lstatSync(source).isDirectory()
const getDirectori...
Forward declaration of a typedef in C++
...
+1 in the end because while you technically can't "forward-typedef" (i.e. you can't write "typedef A;"), you can almost certainly accomplish what the OP wants to accomplish using your trick above.
– j_random_hacker
Apr 30 '09...
gdb: how to print the current line or find the current line number?
...structions- so is tied to assembly concepts.
What you are looking for is called de instruction pointer, i.e:
The instruction pointer register points to the memory address which the processor will next attempt to execute. The instruction pointer is called ip in 16-bit mode, eip in 32-bit mode,an...
Append TimeStamp to a File Name
... to a file using the Path class and string manipulation is not an issue at all. this only an alternative to DateTime.ToString Method (String) or string.Format("{0:yyyy-MM-dd_hh-mm-ss-tt}",DateTime.Now);
– Joseph
Jun 26 '17 at 11:50
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Django DB Settings 'Improperly Configured' Error
...--settings=mysite.settings (or whatever settings module you use)
Set DJANGO_SETTINGS_MODULE environment variable in your OS to mysite.settings
(This is removed in Django 1.6) Use setup_environ in the python interpreter:
from django.core.management import setup_environ
from mysite import settings
s...