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Equivalent of “throw” in R
How does one "throw" an error in R? I have a function that takes a data frame and some column names and does stuff with them. If the columns don't exist, I want the function to stop and to stop all functions depending on it.
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Implode an array with JavaScript?
Can I implode an array in jQuery like in PHP?
7 Answers
7
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How to Get the Current URL Inside @if Statement (Blade) in Laravel 4?
I am using Laravel 4. I would like to access the current URL inside an @if condition in a view using the Laravel's Blade templating engine but I don't know how to do it.
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Find the last element of an array while using a foreach loop in PHP
I am writing a SQL query creator using some parameters. In Java, it's very easy to detect the last element of an array from inside the for loop by just checking the current array position with the array length.
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Calculate relative time in C#
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Jeff, your code is nice but could be clearer with constants (as suggested in Code Complete).
const int SECOND = 1;
const int MINUTE = 60 * SECOND;
const int HOUR = 60 * MINUTE;
const int DAY = 24 * HOUR;
const int MONTH = 30 * DAY;
var ts = new TimeSpan(DateTime.UtcNow.Ticks - yourDate.Ticks);
do...
Convert int to char in java
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int a = 1;
char b = (char) a;
System.out.println(b);
will print out the char with ascii value 1 (start-of-heading char, which isn't printable).
int a = '1';
char b = (char) a;
System.out.println(b);
will print out the ch...
What is the purpose of the word 'self'?
What is the purpose of the self word in Python? I understand it refers to the specific object created from that class, but I can't see why it explicitly needs to be added to every function as a parameter. To illustrate, in Ruby I can do this:
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How to find the port for MS SQL Server 2008?
I am running MS SQL Server 2008 on my local machine. I know that the default port is 1433 but some how it is not listening at this port. The SQL is an Express edition.
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What does Python's eval() do?
In the book that I am reading on Python, it keeps using the code eval(input('blah'))
10 Answers
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How can I use external JARs in an Android project?
...) to my project. I then added the JAR to the build path and checked it off in Order and Export.
12 Answers
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