Tutorial by Examples: le

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 ...

# 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] )...

Tuples support the following build-in functions Comparison If elements are of the same type, python performs the comparison and returns the result. If elements are different types, it checks whether they are numbers. If numbers, perform comparison. If either element is a number, then the other...

Introduction The PHPUnit Manual describes mocking as such: The practice of replacing an object with a test double that verifies expectations, for instance asserting that a method has been called, is referred to as mocking. So instead of stubbing out code, an observer is created that not onl...

// 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...

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...

When more than 9 arguments are supplied, the shift [/n] command can be used, where /n means start at the nth argument, n is between zero and eight. Looping through arguments: :args set /a "i+=1" set arg!i!=%~1 call echo arg!i! = %%arg!i!%% shift goto :args Note, in the above exam...

When multiple variables are defined at the beginning of the batch, a short definition form may be used by employing a replacement string. @echo off set "vars=_A=good,_B=,_E=bad,_F=,_G=ugly,_C=,_H=,_I=,_J=,_K=,_L=,_D=6 set "%vars:,=" & set "%" for /f %%l in ('set _'...

There are two approaches for influencing when a memory cleanup is performed. They are influencing how often the automatic process is performed and the other is manually triggering a cleanup. The garbage collector can be manipulated by tuning the collection thresholds which affect the frequency at w...

If you want to clear your current Activity stack and launch a new Activity (for example, logging out of the app and launching a log in Activity), there appears to be two approaches. 1. Target (API >= 16) Calling finishAffinity() from an Activity 2. Target (11 <= API < 16) Intent intent ...

Get the current date and time. public class Program { static void Main() { // create empty pipeline PowerShell ps = PowerShell.Create(); // add command ps.AddCommand("Get-Date"); // run command(s) Console.WriteLine(&quot...

In order to clear (flush) the entire log: adb logcat -c

ActionMailer supports three callbacks before_action after_action around_action Provide these in your Mailer class class UserMailer < ApplicationMailer after_action :set_delivery_options, :prevent_delivery_to_guests, :set_business_headers Then create these methods under the private ...

Using Ubuntu you have different ways to read a text file, all similar but useful in different context. cat This is the simplest way to read a text file; it simply output the file content inside the terminal. Be careful: if the file is huge, it could take some time to complete the printing process!...

Get all documents in the collection 'myCollection' and print them to the console. const MongoClient = require('mongodb').MongoClient; const url = 'mongodb://localhost:27017/test'; MongoClient.connect(url, function (err, db) { if (err) throw new Error(err); var cursor = db.collection('my...

Delete a document with the property { greetings: 'Whut?' } const MongoClient = require('mongodb').MongoClient; const url = 'mongodb://localhost:27017/test'; MongoClient.connect(url, function (err, db) { if (err) throw new Error(err); db.collection('myCollection').deleteOne(// Delete...

Delete ALL documents with a 'farewell' property set to 'okay'. const MongoClient = require('mongodb').MongoClient; const url = 'mongodb://localhost:27017/test'; MongoClient.connect(url, function (err, db) { if (err) throw new Error(err); db.collection('myCollection').deleteMany(// M...

# The following shell function will be used to generate completions for # the "nuance_tune" command. _nuance_tune_opts () { local curr_arg prev_arg curr_arg=${COMP_WORDS[COMP_CWORD]} prev_arg=${COMP_WORDS[COMP_CWORD-1]} # The "config" option takes a file arg, so ...

If we want to order the data differently for per group, we can add a CASE syntax to the ORDER BY. In this example, we want to order employees from Department 1 by last name and employees from Department 2 by salary. IdFNameLNamePhoneNumberManagerIdDepartmentIdSalaryHireDate1JamesSmith1234567890NUL...