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A tuple is a heterogeneous collection of two to twenty-two values. A tuple can be defined using parentheses. For tuples of size 2 (also called a 'pair') there's an arrow syntax. scala> val x = (1, "hello") x: (Int, String) = (1,hello) scala> val y = 2 -> "world" y:...

The TIMESTAMP column will show when the row was last updated. CREATE TABLE `TestLastUpdate` ( `ID` INT NULL, `Name` VARCHAR(50) NULL, `Address` VARCHAR(50) NULL, `LastUpdate` TIMESTAMP NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP ) COMMENT='Last Update' ;

Code snippet: import java.util.Set; public class ThreadStatus { public static void main(String args[]) throws Exception { for (int i = 0; i < 5; i++){ Thread t = new Thread(new MyThread()); t.setName("MyThread:" + i); t.start(); ...

Sometimes you need to fetch data asynchronously before passing it to a child component to use. If the child component tries to use the data before it has been received, it will throw an error. You can use ngOnChanges to detect changes in a components' @Inputs and wait until they are defined before a...

We consume rest API as a JSON format and then unmarshal it to a POJO. Jackson’s org.codehaus.jackson.map.ObjectMapper “just works” out of the box and we really don’t do anything in most cases. But sometimes we need custom deserializer to fulfill our custom needs and this tutorial will guide you thro...

If you want to show active network interfaces, type: ifconfig If you want to show also network interfaces that are down, type: ifconfig -a

You could use ethtool, but they are not going to be reboot persistent. If you want to achieve this, edit the following file: sudo vim /etc/network/interfaces And edit the file with needed informations: auto <interface_name> iface <interface_name> inet static address <ip_addres...

Using the class below, we can connect to Exchange and then set a specific user's out of office settings with UpdateUserOof: using System; using System.Web.Configuration; using Microsoft.Exchange.WebServices.Data; class ExchangeManager { private ExchangeService Service; public Exch...

x = np.random.random([100,100]) x.tofile('/path/to/dir/saved_binary.npy') y = fromfile('/path/to/dir/saved_binary.npy') z = y.reshape(100,100) all(x==z) # Output: # True

The function np.loadtxt can be used to read csv-like files: # File: # # Col_1 Col_2 # 1, 1 # 2, 4 # 3, 9 np.loadtxt('/path/to/dir/csvlike.txt', delimiter=',', comments='#') # Output: # array([[ 1., 1.], # [ 2., 4.], # [ 3., 9.]]) The same file could be read ...

When data is "tidy," it is often organized into several tables. To combine the data for analysis, we need to "update" one table with values from another. For example, we might have sales data for performances, where attributes of the performer (their budget) and of the location ...

# example data DT = as.data.table(mtcars, keep.rownames = TRUE) To rename a column (while keeping its data the same), there is no need to copy the data to a column with a new name and delete the old one. Instead, we can use setnames(DT, "mpg_sq", "mpq_squared") to modify ...

# example data DT = data.table(iris) To modify factor levels by reference, use setattr: setattr(DT$Species, "levels", c("set", "ver", "vir") # or DT[, setattr(Species, "levels", c("set", "ver", "vir"))] The sec...

# example data set.seed(1) n = 1e7 ng = 1e4 DT = data.table( g1 = sample(ng, n, replace=TRUE), g2 = sample(ng, n, replace=TRUE), v = rnorm(n) ) Matching on one column After the first run of a subsetting operation with == or %in%... system.time( DT[ g1 %in% 1:100] )...

Consider a grid working on some task, e.g. a parallel reduction. Initially, each block can do its work independently, producing some partial result. At the end however, the partial results need to be combined and merged together. A typical example is a reduction algorithm on a big data. A typica...

Consider an array of work items. The time needed for an each work item to complete varies greatly. In order to balance the work distribution between blocks it may be prudent for each block to fetch the next item only when previous one is complete. This is in contrast to a-priori assigning items to...

// application/controllers/Company_controller.php <?php if(!defined('BASEPATH')) exit('No direct script access allowed'); class Company_controller extends CI_Controller { public function __construct() { parent::__construct(); $this->load->model('companies_mo...

If a void* value is converted to a pointer to object type, T*, but is not properly aligned for T, the resulting pointer value is unspecified. Example: // Suppose that alignof(int) is 4 int x = 42; void* p1 = &x; // Do some pointer arithmetic... void* p2 = static_cast<char*>(p1) + 2; ...

To start GDB, in the terminal, gdb <executable name> For the above example with a program named main, the command becomes gdb main Setting Breakpoints You'll probably want you program to stop at some point so that you can review the condition of your program. The line at which you wan...

Batch file command line arguments are parameter values submitted when starting the batch. They should be enclosed in quotes if they contain spaces. In a running batch file, the arguments are used for various purposes, i.e. redirection to :labels, setting variables, or running commands. The argument...