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The ROUND function rounds a value. The number of decimal places to round to is specified by a positive value in the num_digits parameter. A negative value for the num_digits will round the integer portion of the value left of the decimal point, e.g. to the nearest 10 (for -1) or to the nearest 1000 ...

The excel formula TRUNC is used to truncate a number to a given number of decimal places, specified by the optional num_digits parameter. If this parameter is defined as a negative value it will truncate the integer portion of the value. If the parameter is omitted then the default value is 0 which ...

The Excel function MROUND is used to round a number to an interval other than a power of 10. These examples show MROUND to the nearest quarter and to the nearest even number. Starting withMROUND(b,0.25)MROUND(b,2)23.9319521124.00242.7931353882.75221.9390306422.002213.7419373913.751416.7704741216.7...

You need to find out the IP address of the container running in the host so you can, for example, connect to the web server running in it. docker-machine is what is used on MacOSX and Windows. Firstly, list your machines: $ docker-machine ls NAME ACTIVE DRIVER STATE URL ...

Helpful when you want to grab a copy of a production database to play around with locally. mongodump --host some-mongo-host.com:1234 -d DATABASE_NAME -u DATABASE_USER -p DATABASE_PASSWORD This will create a local dump directory; within that directory you'll see a directory with your DATABASE_NAME...

Requirements Python (2.7, 3.2, 3.3, 3.4, 3.5, 3.6) Django (1.7+, 1.8, 1.9, 1.10, 1.11) Install You can either use pip to install or clone the project from github. Using pip: pip install djangorestframework Using git clone: git clone [email protected]:tomchristie/django-rest-framew...

A dotfile is a file whose names begin with a .. These are normally hidden by ls and not listed unless requested. For example the following output of ls: $ ls bin pki The -a or --all option will list all files, including dotfiles. $ ls -a . .ansible .bash_logout .bashrc .lesshst ...

Mage::app()->getStore()->getIsActive();

Matplotlib axes are two-dimensional by default. In order to create three-dimensional plots, we need to import the Axes3D class from the mplot3d toolkit, that will enable a new kind of projection for an axes, namely '3d': import matplotlib.pyplot as plt from mpl_toolkits.mplot3d import Axes3D fi...

If you want two or more arguments to be mutually exclusive. You can use the function argparse.ArgumentParser.add_mutually_exclusive_group(). In the example below, either foo or bar can exist but not both at the same time. import argparse parser = argparse.ArgumentParser() group = parser.add_mut...

If an iterator method has a yield inside a try...finally, then the returned IEnumerator will execute the finally statement when Dispose is called on it, as long as the current point of evaluation is inside the try block. Given the function: private IEnumerable<int> Numbers() { yield re...

To modify an existing column in Rails with a migration, run the following command: rails g migration change_column_in_table This will create a new migration file in db/migration directory (if it doesn’t exist already), which will contain the file prefixed with timestamp and migration file name w...

In Python 3 the cmp built-in function was removed, together with the __cmp__ special method. From the documentation: The cmp() function should be treated as gone, and the __cmp__() special method is no longer supported. Use __lt__() for sorting, __eq__() with __hash__(), and other rich compariso...

Function level annotations help IDEs identify return values or potentially dangerous code /** * Adds two numbers together. * * @param Int $a First parameter to add * @param Int $b Second parameter to add * @return Int */ function sum($a, $b) { return (int) $a + $b; } /** * ...

File level metadata applies to all the code within the file and should be placed at the top of the file: <?php /** * @author John Doe ([email protected]) * @copyright MIT */

If a class extends another class and would use the same metadata, providing it @inheritDoc is a simple way for use the same documentation. If multiple classes inherit from a base, only the base would need to be changed for the children to be affected. abstract class FooBase { /** * @par...

Let's say you need to implement an automatic search box, but the search operation is somewhat costly, like sending a web request or hitting up a database. You may want to limit the amount of search being done. For example, the user is typing "C# Reactive Extensions" in the search box : I...

There are two operators for filtering duplicates: emails.Distinct(); // Never see the same value twice emails.DistinctUntilChanged(); // Never see the same value twice in a row You can also pass in a predicate: emails.DistinctUntilChanged(x => x.Length); // Never see the same length email t...

In order to define a variable inside a linq expression, you can use the let keyword. This is usually done in order to store the results of intermediate sub-queries, for example: int[] numbers = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }; var aboveAverages = from number in numbers l...

# load the library library(ggplot2) # create a blank canvas g <- ggplot(data = diamonds) g + geom_bar(aes(x = cut, fill = cut)) + scale_fill_discrete(guide = guide_legend(title = "CUT", keywidth = 2, ...