jebright

import 'dart:async';
import 'package:flutter/material.dart';
import 'dart:isolate';

void main() => runApp(new MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(

mraleph

Dart VM FFI Vision

Background

The aim of Dart FFI project (tracked as Issue #34452) is to provide a low boilerplate, low ceremony & low overhead way of interoperating with native C/C++ code.

The motivation behind this project is twofold:

steven2358

FFmpeg cheat sheet

A list of useful commands for the FFmpeg command line tool.

Download FFmpeg: https://www.ffmpeg.org/download.html

Full documentation: https://www.ffmpeg.org/ffmpeg.html

Basic conversion

Spindel

#!/bin/env python3
import os
import mmap
import logging
import hashlib
import contextlib
log = logging.getLogger(__name__)

@contextlib.contextmanager
def directio_mmap(filename, readsize, offset):

nzw0301

*2vec papers

1. act2vec, trace2vec, log2vec, model2vec https://link.springer.com/chapter/10.1007/978-3-319-98648-7_18
2. apk2vec https://arxiv.org/abs/1809.05693
3. app2vec http://paul.rutgers.edu/~qma/research/ma_app2vec.pdf
4. ast2vec https://arxiv.org/abs/2103.11614
5. attribute2vec https://arxiv.org/abs/2004.01375
6. author2vec http://dl.acm.org/citation.cfm?id=2889382
7. baller2vec https://arxiv.org/abs/2102.03291
8. bb2vec https://arxiv.org/abs/1809.09621

justusranvier

SPV clients lack the ability of full nodes to detect whether or not a chain provided to them by another source complies with the rules of the Bitcoin protocol.

SPV clients can connect to multiple full nodes in the hope that at least one of the nodes is honest and will provide them with the best valid chain, however situations may arise where the non-compliant chain contains more proof of work than the compliant chain. In this situation, there is no way for the honest full node to signal to an SPV client that it should disregard the chain with more proof of work.

Fraud proofs are a technique which provide honest full nodes the capability to conclusively demonstrate that chain is invalid regardless of the amount of proof of work backing the invalid chain.

If Bitcoin nodes implement the ability to create, propagate, and verify fraud proofs, the security of SPV clients will be improved.

Assumptions and Definitions

oleganza

(That's my attempt to understand what problem Impulse solves and how. I am not a designer/developer of this scheme.)

Problem

Regular Bitcoin transactions are not guaranteed until mined sufficiently deep in the blockchain. Unconfirmed transactions can be observed nearly instantly, but they cannot be trusted (could drop out because of insufficient fees, or double-spent).

Impulse Overview

malcolmboyd

#!/usr/bin/python3
import requests, subprocess, time, smtplib

from email.mime.text import MIMEText
from bs4 import BeautifulSoup

class BitcoinPrice:
    price = 0
    website = "http://www.bitcoinexchangerate.org/"

gavinandresen

O(1) Block Propagation

The problem

Bitcoin miners want their newly-found blocks to propagate across the network as quickly as possible, because every millisecond of delay increases the chances that another block, found at about the same time, wins the "block race."

fragoulis

À	A
Á	A
Â	A
Ã	A
Ä	A
Å	A
Æ	A
à	a
á	a
â	a