DmitriyVlasov

Architecture

• Use Onion architecture

  • Dependencies go inwards. That is, the Core domain doesn't know about outside layers

• Use pipeline model to implement workflows/use-cases/stories

  • Business logic makes decisions
  • IO does storage with minimal logic
  • Keep Business logic and IO separate

• Keep IO at edges

DmitriyVlasov

USE [master]
GO

IF OBJECT_ID('dbo.calendar') IS NOT NULL
  DROP TABLE [dbo].[calendar];

IF OBJECT_ID('dbo.fn_generate_calendar') IS NOT NULL 
  DROP FUNCTION [dbo].[fn_generate_calendar];
GO

DmitriyVlasov

ffmpeg

Converting Audio into Different Formats / Sample Rates

Minimal example: transcode from MP3 to WMA:
ffmpeg -i input.mp3 output.wma

You can get the list of supported formats with:
ffmpeg -formats

Convert WAV to MP3, mix down to mono (use 1 audio channel), set bit rate to 64 kbps and sample rate to 22050 Hz:

DmitriyVlasov

Sparkline Line = 

// Static line color - use %23 instead of # for Firefox compatibility
VAR LineColor = "%2301B8AA"

// "Date" field used in this example along the X axis
VAR XMinDate = MIN('Table'[Date])
VAR XMaxDate = MAX('Table'[Date])

// Obtain overall min and overall max measure values when evaluated for each date

DmitriyVlasov

// killerDateTableRu
// функция killerDateTableRu создает таблицу с датами. Дополняет ее различными полезными для Time Intelligence столбцами. 
// В случае, если четвертый аргумент принимает Дни 1, то функция добавляет столбец с выходными.
// Оригинальная идея philbritton https://gist.github.com/philbritton/9677152
// пример: killerDateTableRu(#date(2017, 2, 1), #date(2017, 2, 4), "RU-ru", 1)

// Описание полей результирующей таблицы:
// ===================================================
// Date - дата
// Year - год

DmitriyVlasov

#I "../lib"
#r "FSharp.Markdown.dll"
#r "FSharp.Literate.dll"
#r "Deedle.dll"

open System.IO
open Deedle
open Deedle.Internal
open FSharp.Literate
open FSharp.Markdown

DmitriyVlasov

OS X Screencast to animated GIF

This gist shows how to create a GIF screencast using only free OS X tools: QuickTime, ffmpeg, and gifsicle.

Instructions

To capture the video (filesize: 19MB), using the free "QuickTime Player" application:

DmitriyVlasov

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

DmitriyVlasov

//------------------------------------------
// Step 0. Boilerplate to get the paket.exe tool
 
open System
open System.IO
 
Environment.CurrentDirectory <- __SOURCE_DIRECTORY__
 
if not (File.Exists "paket.exe") then
    let url = "http://fsprojects.github.io/Paket/stable"

DmitriyVlasov

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

namespace Utility