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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
...just changing the elements that need to be changed. That's important to avoid for large data, and why := and set() were introduced to data.table.
Now, with our copied newDT we can modify it by reference :
newDT
# a b
# [1,] 1 11
# [2,] 2 200
newDT[2, b := 400]
# a b # See FA...
Check if a value is within a range of numbers
... I appreciate what you're saying, but I suggest that you may want to reconsider the premise that people here generally "know what they are asking for." That may be true in a very narrow sense, but often these questions reflect some bad design decision that should be revisited. I've been answering p...
Git - What is the difference between push.default “matching” and “simple”
...ferent from default.
Push only the current branch if its named upstream is identical
git config --global push.default simple
So, it's better, in my opinion, to use this option and push your code branch by branch. It's better to push branches manually and individually.
...
How to redirect cin and cout to files?
...clude <iostream>
#include <fstream>
#include <string>
void f()
{
std::string line;
while(std::getline(std::cin, line)) //input from the file in.txt
{
std::cout << line << "\n"; //output to the file out.txt
}
}
int main()
{
std::ifstream i...
Maven: how to override the dependency added by a library
...cify the version in your current pom. The version specified here will override other.
Forcing a version
A version will always be honoured if it is declared in the current POM with a particular version - however, it should be noted that this will also affect other poms downstream if it is itsel...
How to append text to a text file in C++?
...s created if it doesn't exist and also adds bit of error checks.
static void appendLineToFile(string filepath, string line)
{
std::ofstream file;
//can't enable exception now because of gcc bug that raises ios_base::failure with useless message
//file.exceptions(file.exceptions() | std:...
Git: How to edit/reword a merge commit's message?
...This happens because you modified commits that you already sent. It is considered bad practice to force push to a server since it can completely desync you and your co-workers. Well, if you're alone it should not be a problem.
– ibizaman
Jan 14 '14 at 8:56
...
Objective-C declared @property attributes (nonatomic, copy, strong, weak)
... answered Mar 25 '12 at 12:58
iDhavaliDhaval
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...
Optimal settings for exporting SVGs for the web from Illustrator?
...SVG Viewer
Adobe SVG Viewer is a browser plugin from times when browsers did not support SVG natively. I don't know what it does, but it is irrelevant, do not check this.
Include slicing data
This adds metadata bloat to your SVG file, unless you plan on opening your SVG file later in Illustrator ...
Relatively position an element without it taking up space in document flow
...and, you can, however, make a pseudo-relative element, by creating a zero-width, zero-height, relatively positioned element, essentially solely for the purpose of creating a reference point for position, and an absolutely positioned element within that:
<div style="position: relative; width: 0; ...