Tutorial by Examples: d

When an exception is thrown from within a Future, you can (should) use recover to handle it. For instance, def runFuture: Future = Future { throw new FairlyStupidException } val itWillBeAwesome: Future = runFuture ...will throw an Exception from within the Future. But seeing as we can predic...

.message color: white .message-important @extend .message background-color: red This will take all of the styles from .message and add them to .message-important. It generates the following CSS: .message, .message-important { color: white; } .message-important { background-...

.message color: white .important background-color: red .message-important @extend .message, .important In the above code @extend is used in one line to add multiple classes' code to .message-important, however, it is possible to use one extend per line like this: .message-importan...

.message color: white background: black .message-important @extend .message font-weight: bold .message-error @extend .message-important font-style: italic This code causes .message-error to extend from .message-important, which means that it will contain code from both .me...

Sometimes, you may want an @extend to be optional, and not require the specified class to exist in your code. .message-important @extend .message !optional background: red This will result in the following CSS: .message-important { background: red; } Disclaimer: This is useful duri...

If the file does not contain a header row, File: 1;str_data;12;1.4 3;str_data;22;42.33 4;str_data;2;3.44 2;str_data;43;43.34 7; str_data; 25; 23.32 you can use the keyword names to provide column names: df = pandas.read_csv('data_file.csv', sep=';', index_col=0, ski...

generate sample data frames: In [57]: df3 = pd.DataFrame({'col1':[211,212,213], 'col2': [221,222,223]}) In [58]: df1 = pd.DataFrame({'col1':[11,12,13], 'col2': [21,22,23]}) In [59]: df2 = pd.DataFrame({'col1':[111,112,113], 'col2': [121,122,123]}) In [60]: df3 = pd.DataFrame({'col1':[211,2...

import string import numpy as np import pandas as pd generate sample DF with various dtypes df = pd.DataFrame({ 'int32': np.random.randint(0, 10**6, 10), 'int64': np.random.randint(10**7, 10**9, 10).astype(np.int64)*10, 'float': np.random.rand(10), 'string': ...

import os, time import pyodbc import pandas.io.sql as pdsql def todf(dsn='yourdsn', uid=None, pwd=None, query=None, params=None): ''' if `query` is not an actual query but rather a path to a text file containing a query, read it in instead ''' if query.endswith('.sql') and o...

The pattern matching library trivia provides a system trivia.ppcre that allows captured groups to be bound through pattern matching (trivia:match "John Doe" ((trivia.ppcre:ppcre "(.*)\\W+(.*)" first-name last-name) (list :first-name first-name :last-name last-name))) ;...

wget http://download.redis.io/redis-stable.tar.gz tar xvzf redis-stable.tar.gz cd redis-stable make

redis-server

redis-cli ping This should return PONG

The .indexOf method returns the index of a substring inside another string (if exists, or -1 if otherwise) 'Hellow World'.indexOf('Wor'); // 7 .indexOf also accepts an additional numeric argument that indicates on what index should the function start looking "harr dee harr dee harr&quot...

The ANSI CL standard uses an extended EBNF syntax notation. The documentation duplicated on Stackoverflow should use the same syntax notation to reduce confusion. Example: specialized-lambda-list::= ({var | (var parameter-specializer-name)}* [&optional {var | (var [initform [supp...

To create a human-readable presentation of a model object you need to implement Model.__str__() method (or Model.__unicode__() on python2). This method will be called whenever you call str() on a instance of your model (including, for instance, when the model is used in a template). Here's an exampl...

itertools.combinations will return a generator of the k-combination sequence of a list. In other words: It will return a generator of tuples of all the possible k-wise combinations of the input list. For Example: If you have a list: a = [1,2,3,4,5] b = list(itertools.combinations(a, 2)) print ...

import java.io.*; import java.net.Socket; public class Main { public static void main(String[] args) throws IOException {//We don't handle Exceptions in this example //Open a socket to stackoverflow.com, port 80 Socket socket = new Socket("stackoverflow.com",8...

- initWithCalendarIdentifier: Initializes a newly-allocated NSCalendar object for the calendar specified by a given identifier. NSCalendar *calender = [[NSCalendar alloc]initWithCalendarIdentifier:@"gregorian"]; NSLog(@"%@",calender); - setFirstWeekday: Sets the index of the...

- components:fromDate: Returns a NSDateComponents object containing a given date decomposed into specified components NSCalendar *calender = [NSCalendar autoupdatingCurrentCalendar]; [calender setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]]; NSLog(@"%@",[calender components:NSCale...