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Extract month and year from a zoo::yearmon object
... I'd add a zoo-free answer for ts as well.
# create an example Date
date_1 <- as.Date("1990-01-01")
# extract year
as.numeric(format(date_1, "%Y"))
# extract month
as.numeric(format(date_1, "%m"))
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What differences, if any, between C++03 and C++11 can be detected at run-time?
...led with a C++ compiler, will return 1 (the trivial sulution with
#ifdef __cplusplus is not interesting).
8 Answers
...
How to implement Enums in Ruby?
...to enhance readability without littering code with literal strings.
postal_code[:minnesota] = "MN"
postal_code[:new_york] = "NY"
Constants are appropriate when you have an underlying value that is important. Just declare a module to hold your constants and then declare the constants within that.
...
App Inventor 2 SemiCircleArc 扩展：高级自定义半圆进度条 · App Inventor 2 中文网
...：
when Screen1.Initialize() {
SemiCircleArc1.Initialize(垂直布局_进度)
SemiCircleArc1.ShowProgressText = true
SemiCircleArc1.LabelText = "加载中"
SemiCircleArc1.ProgressBarGradient(&HFF42A5F5, &HFF7E57C2)
SemiCircleArc1.BackgroundGradient(&HFFE0E0E0, &HFFF5F5F5)
SemiCircleArc...
What is the relative performance difference of if/else versus switch statement in Java?
...view a switch statement as follows:
switch (<condition>) {
case c_0: ...
case c_1: ...
...
case c_n: ...
default: ...
}
where c_0, c_1, ..., and c_N are integral numbers that are targets of the switch statement, and <condition> must resolve to an integer expression.
I...
printf with std::string?
... for some reason, you need to extract the C-style string, you can use the c_str() method of std::string to get a const char * that is null-terminated. Using your example:
#include <iostream>
#include <string>
#include <stdio.h>
int main()
{
using namespace std;
string my...
How to unzip a file using the command line? [closed]
...mmand "Expand-Archive '.\file.zip' '.\unziped\'"
– AK_
Mar 17 '18 at 21:11
@AK_ what about Windows 8 or 8.1?
...
Selenium wait until document is ready
...it" function (use a WebDriverWait if you like, I find them ugly):
def wait_for(condition_function):
start_time = time.time()
while time.time() < start_time + 3:
if condition_function():
return True
else:
time.sleep(0.1)
raise Exception('Timeout...
Sorting a tab delimited file
... Ruby. Here's some example code:
#!/usr/bin/perl -w
use strict;
my $sort_field = 2;
my $split_regex = qr{\s+};
my @data;
push @data, "7 8\t 9";
push @data, "4 5\t 6";
push @data, "1 2\t 3";
my @sorted_data =
map { $_->[1] }
sort { $a->[0] <=> $b->[0] }
map { [ ( sp...
Where can I view Tomcat log files in Eclipse?
... "Arguments" tab of its launch configuration:
-Dcatalina.base="${project_loc}\<apache-tomcat-5.5.23_loc>"
-Dcatalina.home="${project_loc}\<apache-tomcat-5.5.23_loc>"
-Djava.util.logging.config.file="${project_loc}\<apache-tomcat-5.5.23_loc>\conf\logging.properties"
-Djava.uti...