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bundler vs RVM vs gems vs RubyGems vs gemsets vs system ruby [closed]
...f Ruby (it is itself packaged as a gem), but it a "de facto standard" for most applications (you will not find many people not using it, and no good reasons not to use it, actually).
RVM is a tool allowing you to install multiple versions of Ruby on a machine, switching between them when needed. Th...
How to read a file without newlines?
... only works if the file ends with a newline, otherwise the last line will lose a character.
This assumption is true in most cases (especially for files created by text editors, which often do add an ending newline anyway).
If you want to avoid this you can add a newline at the end of file:
with o...
Is MonoTouch now banned on the iPhone? [closed]
A recent post by John Gruber notes that the following legalese:
18 Answers
18
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How to make a countdown timer in Android?
...
MainActivity.java
package com.zeustechnocrats.countdown;
import android.os.Bundle;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.TextView;
import java.text.SimpleDateFormat;
import j...
How do I convert a double into a string in C++?
...
The boost (tm) way:
std::string str = boost::lexical_cast<std::string>(dbl);
The Standard C++ way:
std::ostringstream strs;
strs << dbl;
std::string str = strs.str();
Note: Don't forget #include <sstream>
...
How do I rename all files to lowercase?
... user2066039: This must must be a recent thing on the Mac, because most answers older than a year don't account for it. I accomplished the task by using an intermediate extension like 'jpg1'. So, JPG -> jpg1 -> jpg. Hope that helps.
– Joyce
Nov 1 '...
How do I make a Mac Terminal pop-up/alert? Applescript?
...ice, whatever that displays my custom text. How is this done? Also, is it possible to make one with several buttons that sets a variable?
...
What's the fastest way to merge/join data.frames in R?
...bases as well.
library(plyr)
library(data.table)
library(sqldf)
set.seed(123)
N <- 1e5
d1 <- data.frame(x=sample(N,N), y1=rnorm(N))
d2 <- data.frame(x=sample(N,N), y2=rnorm(N))
g1 <- sample(1:1000, N, replace = TRUE)
g2<- sample(1:1000, N, replace = TRUE)
d <- data.frame(d1, g1,...
Why do I get “Pickle - EOFError: Ran out of input” reading an empty file?
...
I would check that the file is not empty first:
import os
scores = {} # scores is an empty dict already
if os.path.getsize(target) > 0:
with open(target, "rb") as f:
unpickler = pickle.Unpickler(f)
# if file is not empty scores will be equal
...
std::string to float or double
...to convert a string to a double.
You can do it with the stringstream or boost::lexical_cast but those come with a performance penalty.
Ahaha you have a Qt project ...
QString winOpacity("0.6");
double temp = winOpacity.toDouble();
Extra note:
If the input data is a const char*, QByteArray::to...