import urllib2
import json
import numpy as np
import matplotlib.pyplot as plt
from pprint import pprint


def showInfo(address):
  response = urllib2.urlopen('https://blockchain.info/address/' + address + '?format=json')
  data = response.read()

  val = []
  data = json.loads(data)

  print data['address']
  print data['total_received']
  print data['total_sent']

showInfo("1E6dum2sxdctc9hMV1Dk1xd8Vang3u9EA2")

Save the file as example.py and run

python example.py

The total_received and total_sent are shown in Satoshi (the smallest unit).  Thus the output 2456674  means 0.02456674 BTC

We then extend it to display information of a block:

import urllib2
import json
import numpy as np
import matplotlib.pyplot as plt
from pprint import pprint
 

def showInfo(address): 
  response = urllib2.urlopen('https://blockchain.info/address/' + address + '?format=json')
  data = response.read()

  val = []
  data = json.loads(data)

  print data['address']
  print data['total_received']
  print data['total_sent'] 

def showBlock(block):

  response = urllib2.urlopen('https://blockchain.info/rawblock/' + block + '?format=json')
  data = response.read()

  val = []
  data = json.loads(data)

  print '-----------------------------'
  print 'Block index: \t\t',
  print data['block_index']

  print 'Previous block:\t\t',
  print data['prev_block']

  print 'Time:\t\t\t',
  print data['time']
 
  print 'Nr. Transactions:\t',
  print data['n_tx']


  print '------------------------------'
showBlock('00000000000009fdb874661ff1c08f0a2d082aa788a5b90fbd428ce3622e121c')
#showInfo("1E6dum2sxdctc9hMV1Dk1xd8Vang3u9EA2")

This will output:

-----------------------------
Block index: 		169563
Previous block:		0000000000000753b0a49656f0105c317851f7c2b3945eea0c272499547af433
Time:			1322128192
Nr. Transactions:	27
------------------------------

If you want to see the Genisis block, the id is 000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f

Further reading: https://blockchain.info/api/blockchain_api

import json
import numpy as np
import matplotlib.pyplot as plt
from pprint import pprint


def getPrices(filename):
  val = []

  with open(filename) as data_file:
    data = json.load(data_file)

  for v in data["price_usd_data"]:
    print v[1]
    val.append(v[1])

  return val

btc = getPrices("bitcoin.json")
plt.plot(btc)
plt.show()

Simply get the JSON data http://coinmarketcap.com/static/generated_pages/currencies/datapoints/bitcoin-365d.json

You can plot multiple charts in one using this little trick:

btc = getPrices("bitcoin-365.json")
btc = getPrices("litecoin-365.json")
plt.plot(btc)
plt.plot(ltc)
plt.show()

The program outputs graphs like this:

litecoin vs darkcoin

If the market price data is too far apart, you will get strange plots.  Furthermore, you are not limited to this kind of plots

Currently supported exchanges are:

• Bitstamp (USD)
• Bitcoin24 (EUR)
• Paymium (USD, EUR)
• BTC-e (USD, EUR)
• Bitfinex (USD)
• Kraken (USD, EUR)
• OkCoin (CNY)
• CampBX (USD)

To install and run:

git clone https://github.com/maxme/bitcoin-arbitrage.git
cd bitcoin-arbitrage/
cp arbitrage/config.py-example arbitrage/config.py
python3 arbitrage.py 

It could give some errors, but nothing important.  The program will automatically output opportunities; At the time of running, we got these:

2014-12-06 17:52:39,729 [INFO] profit: 17.555133 USD with volume: 10.000000 BTC - buy from KrakenEUR sell to PaymiumEUR ~0.46%
2014-12-06 17:52:39,731 [INFO] profit: 0.511115 USD with volume: 4.195000 BTC - buy from KrakenEUR sell to BitfinexUSD ~0.03%
2014-12-06 17:52:49,831 [INFO] profit: 30.132266 USD with volume: 10.000000 BTC - buy from BtceUSD sell to KrakenEUR ~0.81%
2014-12-06 17:52:49,854 [INFO] profit: 70.126539 USD with volume: 10.000000 BTC - buy from BtceUSD sell to PaymiumEUR ~1.88%
2014-12-06 17:52:49,878 [INFO] profit: 6.898993 USD with volume: 10.000000 BTC - buy from BtceUSD sell to KrakenUSD ~0.19%
2014-12-06 17:52:50,245 [INFO] profit: 34.493657 USD with volume: 10.000000 BTC - buy from BtceUSD sell to BitstampUSD ~0.92%
2014-12-06 17:52:51,636 [INFO] profit: 53.063079 USD with volume: 10.000000 BTC - buy from BtceUSD sell to BitfinexUSD ~1.42%
2014-12-06 17:52:51,638 [INFO] profit: 26.339595 USD with volume: 10.000000 BTC - buy from BitstampUSD sell to PaymiumEUR ~0.70%
2014-12-06 17:52:51,643 [INFO] profit: 9.276136 USD with volume: 10.000000 BTC - buy from BitstampUSD sell to BitfinexUSD ~0.25%
2014-12-06 17:52:51,643 [INFO] profit: 9.831532 USD with volume: 10.000000 BTC - buy from BitfinexUSD sell to PaymiumEUR ~0.26%

Profits are anywhere between 0.50 $ and 70.00 $ with a trade volume of 10 BTC ( 3699.64 $ currently )

 
Coinkit script
Coinkit is a Python library with tools for Bitcoin and other cryptocurrencies. It is currently in Beta but it aims to support Bitcoin, Litecoin, Namecoin, Peercoin, Primecoin, Testnet, Worldcoin, Megacoin, Feathercoin, Terracoin, Novacoin, Dogecoin, Anoncoin, Protoshares, Ixcoin, Memorycoin, Infinitecoin, Cryptogenic Bullion, Quarkcoin, Netcoin, Earthcoin, Reddcoin,

sudo pip install coinkit

Open up your favourite text editor and paste this code:

from coinkit import *

priv = BitcoinPrivateKey()
bitcoin_pub = priv.public_key()
bitcoin_address = bitcoin_pub.address()

litecoin_priv = LitecoinPrivateKey(priv.to_hex())
litecoin_pub = litecoin_priv.public_key()
litecoin_address = litecoin_pub.address()

namecoin_priv = NamecoinPrivateKey(priv.to_hex())
namecoin_pub = namecoin_priv.public_key()
namecoin_address = namecoin_pub.address()

print ""
print "Receiving address"
print "bitcoin  : " + bitcoin_address
print "litecoin : " + litecoin_address
print "namecoin : " + namecoin_address

print ""
print "Private keys "
print "bitcoin  : " + priv.to_wif()
print "litecoin : " + litecoin_priv.to_wif()
print "namecoin : " + namecoin_priv.to_wif()
print ""

Save it as create.py and run

python create.py

The output should be something like this:

Receiving address
bitcoin  : 1AyPpKpsraPA2DVbne6atxB5ExC1k435ea
litecoin : LVCM5Y8hwEdDH2Bkxn5tAyEqTAZHp7FPzX
namecoin : N6Ym1yKrmxUiYkk74TRA7UKyyBb4djTozU

Private keys 
bitcoin  : ************************************
litecoin : ************************************
namecoin : ************************************

You can create a QR code for an address using this command:

qrencode YOUR_RECEIVAL_ADDRESS -o image.png

Vanitygen
Vanitygen can generate regular bitcoin addresses, namecoin addresses, and testnet addresses. Using some tricks we can generate other addresses too. Install vanitygen using:

# git clone https://github.com/samr7/vanitygen
# cd vanitygen
# make

Once compilation has finished, copy this script:

#!/bin/bash

echo "-----------------------------------"
echo "Bitcoin"
echo "-----------------------------------"
./vanitygen 1

echo "-----------------------------------"
echo "Namecoin"
echo "-----------------------------------"
./vanitygen -N NAME

echo "-----------------------------------"
echo "Litecoin"
echo "-----------------------------------"
./vanitygen -X 48 L

echo "-----------------------------------"
echo "Peercoin"
echo "-----------------------------------"
./vanitygen -X 55 PWn3d

echo "-----------------------------------"
echo "Dogecoin"
echo "-----------------------------------"
./vanitygen -X 30 DBone

Save it as create.sh, then:

chmod 755 create.sh
./create.sh

It will create a bitcoin, litecoin, peercoin, dogecoin and namecoin address with private key.

First grab the source code of Vanitygen from https://github.com/samr7/vanitygen either download the zip or use git. Then enter these commands:

unzip vanitygen-master.zip 
cd vanitygen-master/
make

This will compile the Vanitygen source code.  Once installed we can create a custom bitcoin address. All bitcoin addresses start with the number one. We enter this command:

./vanitygen 1Tux

After a second or so we get our bitcoin address:

Difficulty: 4553521
Pattern: 1Tux                                                                  
Address: 1TuxhRxTzHUfoHrZiUjUBLX4XUf8ANovn
Privkey: ------------------------------------

Another example:

$ ./vanitygen 1Love
Difficulty: 4476342
[48165 K/s][total 2080000][Prob 37.2%][50% in 21.2s]                           
Pattern: 1Love
Address: 1LoveRg5t2NCDLUZh6Q8ixv74M5YGVxXaN
Privkey: 5JLUmjZiirgziDmWmNprPsNx8DYwfecUNk1FQXmDPaoKB36fX1o

Now you have your custom bitcoin wallet.  You can import it to your desktop wallet or simply use it like this.

• create wallet
• check balance
• send transactions

The program will start by asking the user for a brainwallet password. From this password the public key, private key and address are generated.

from pybitcointools import *


class Wallet:

        priv = ""
        pub = ""
        address = ""

        def createWallet(self,brainwalletpassword):
                priv = sha256(brainwalletpassword)
                pub = privtopub(priv)
                address = pubtoaddr(pub)

                print "Address : " + address


x = Wallet()

password = raw_input("Your brain wallet password: ")
x.createWallet(password)

Now we will add the functionality to view the current balance. This is a simple function:

def balance(self):
                print unspent(self.address)

Simply call x.balance() to use it.  We did not send any btc to this wallet, which is what you need to do now to test the functionality of sending BTC. We make a small transaction to this bitcoin wallet and send a tiny amount to our brainwallet. We view blockchain.info to see we have received the transaction (type your address), and we wait until it is fully confirmed. Let us implement the code to send the BTC:

from pybitcointools import *


class Wallet:

	priv = ""
	pub = ""
	address = ""

	def createWallet(self,brainwalletpassword):
		self.priv = sha256(brainwalletpassword)
		self.pub = privtopub(self.priv)
		self.address = pubtoaddr(self.pub)

		print "Address : " + self.address

	def balance(self):
		print unspent(self.address)

	def sendBTC(self,dst, amount):
		h = history(self.address)
		#print h
		outs = [{'value': amount, 'address': dst}] 
		tx = mksend(h,outs, self.address, 10000)
		tx2 = sign(tx,0,self.priv)
		pushtx(tx2)

x = Wallet()

password = raw_input("Your brain wallet password: ")
x.createWallet(password)

x.balance()

x.sendBTC('1A1bBJwQMsbEbdyAnfe1ESvVAM3hmB6fSC', 20000)

(yes, we can send bitcoin in pure python). We added the function sendBTC which has the parameters destination address and amount (We hard-coded the fee).  Note that the bitcoin network only knows about the smallest unit (satoshi), and not about mBTC, kBTC, bits or BTC.    We hard-coded the fee to 10000.   We hardcoded 20000 as the amount of satoshi we sent.  In order to make a transaction, you must sign it with your private key. Finally we call pushtx which broadcasts the transaction to the bitcoin network.  Upon viewing your wallet again on any blockchain explorer  blockchain.info  you should see your (unconfirmed) transaction appearing.

Finding the transaction on blockchain.info

What’s next? You should do proper error handling, secure the wallet, create the ability for backups, create some form of a user interface, and the list goes on :). Pybitcointools relies on blockchain.info for sending bitcoins;

Are you a sysadmin, software developer, linux guru? Have you ever dreamt to build the worlds biggest bitcoin exchange? Do you want to create an online marketplace? This article will help you to get started with your exciting new bitcoin project!

Let us take some of the latest bitcoin software tools:

• zbar-tools
• pybitcointools
• python-trezor
• python-mnemonic
• bitcoin-bash tools

zbar-tools
ZBar is an open source software suite for reading bar codes from various sources.  QR codes are very popular amongst the bitcoin community. You can either compile zbar from source  (bzip2 -d zbar.tar.bz2; tar xvf zbar.tar; ./configure; make)  or right from the repository:

$ sudo apt-get install zbar-tools

Once installed we can get the text from a QR code using the command:

$ zbarimg qrcode.png

tip : try it with the image you created with qrencode in the previous tutorial

You can get the output in the XML format using:

$ zbarimg qrcode.png –xml

pybitcointools
An API that combines the power of Python and Bitcoin?  This sounds very promising.  We install using:

sudo pip install pybitcointools

Pybitcointools is not a full node, it has no idea what blocks are. It relies on centralized service (blockchain.info) for blockchain operations. This should not be a problem, but keep this in mind;

We write the first program, which simply fetches the account transaction history from the blockchain (through blockchain.info). Openup your favourite editor and paste:

from pybitcointools import *

addr = “1A1bBJwQMsbEbdyAnfe1ESvVAM3hmB6fSC”
h = history(addr)
print h

Save the file as example.py and execute it with

python example.py

The program will output the list of transactions for the bitcoin address 1A1bBJwQMsbEbdyAnfe1ESvVAM3hmB6fSC. Pretty neat, eh?

Now we will do some cool stuff with a brain wallet.  Open https://brainwallet.github.io/  and type a passphrase to generate an address. In my case I took a very weak password “hello world”. You will see the private key and public key being generated on the fly. Use this as a reference later on; We will create a program now which can generate the public and private key directly from this password. In addition, we will create the bitcoin address from the public key.

from pybitcointools import *

priv = sha256(‘hello world’)
pub = privtopub(priv)
address = pubtoaddr(pub)

print “Private key: ” + priv
print “Public key : ” + pub
print “Address : ” + address

This bitcoin address will obviously not have any transaction history. The complete list of commands can be found at: https://github.com/vbuterin/pybitcointools

python-trezor
Remember the hardware wallet Trezor we discussed? You can interact with it using python. Install using:

sudo apt-get install python-dev python-setuptools cython
git clone https://github.com/trezor/python-trezor.git
cd python-trezor
python setup.py install (or develop)

Then follow the instructions on https://github.com/trezor/python-trezor  and http://www.bitcointrezor.com/

python-mnemonic

This library  can be used for generating the mnenomic, and converting it into a binary seed. This seed can be later used to generate deterministic wallets using BIP-0032 or similar methods.
First install the python package pbkdf2, it is a dependency.

sudo pip install pbkdf2

Clone the python-mnemonic package using:

git clone https://github.com/trezor/python-mnemonic

You should have git installed. If not, install git. Next, enter these commands:

cd python-mnemonic/

python test_mnemonic.py

This will execute some tests, should work fine.  Remove vectors.json using

rm -r vectors.json

Run the example using

generate_vectors.py

The passphrase “TREZOR” is used for all vectors.  Read more on https://github.com/trezor/python-mnemonic

bitcoin-bash tools
First clone the package using the command

git clone https://github.com/grondilu/bitcoin-bash-tools

Let us do the next steps:

cd bitcoin-bash-tools/

vim test.sh

Paste this code

#!/bin/bash
source bitcoin.sh

newBitcoinKey

Then save it.  Run

chmod 755 test.sh

./test.sh

It will generate a secret key, public exponent and a bitcoin address. To see the complete list of commands open https://github.com/grondilu/bitcoin-bash-tools

• bitcoin native (very good, but wont be discussed here)
• qrencode
• sx

qrencode
The qrencode application is a tool to quickly produce qrcodes. Generating a QR code, a type of matrix barcode, for a bitcoin address from the command line :

$ sudo apt-get install qrencode
$ qrencode 125tQCeg89h8d3ccgBsipbjGUJpqx4c3H1 -o qrcode.png
$ display qrcode.png   (optional, display it)

This will output a QR code image of 111×111 pixels.  You can change the size of the dots, thus making the image larger using the -s command.

$ qrencode 125tQCeg89h8d3ccgBsipbjGUJpqx4c3H1 -s 6 -o qrcode.png
$ display qrencode.png

sx tools
sx is a set of modular Bitcoin commandline utilities. First clone libbitcoin from https://github.com/libbitcoin/libbitcoin#debianubuntu  and run

cd libbitcoin-version2
sudo install.sh

Installing command line tool sx :

wget https://github.com/spesmilo/sx/raw/master/install-sx.sh
sudo apt-get install bignum
sudo apt-get install sudo apt-get install libgmp-dev
chmod 755 install-sx.sh
sudo bash ./install-sx.sh

Installation will take a while, expect around 30 minutes installation time. It will download a lot of packages and compile them from source. This should work on latest versions of Debian Linux or Ubuntu Linux.

If that did not work try to download the packages into your /Downloads/ directory.

• libbitcoin 2.0
• libwallet 0.4
• Obelisk 1.0

Open a console and for each of the packages type

$ bzip2 -d filename.tar.bz2
$ tar xvf filename.tar
$ cd filename
$ autoreconf -i
$ ./configure
$ make
$ sudo make install
$ sudo ldconfig

( You might need sudo apt-get -f install libzmq-dev  and sudo apt-get install libcrypto* )

Finally download sx from  here:

• sx 1.0

Run the commands:

sh ./install-sx.sh

If you get an error about leveldb_blockchain, this error to be exact:

initchain.cpp:19:5: error: ‘leveldb_blockchain’ was not declared in this scope
leveldb_blockchain chain(pool);

Then add the line

#include <bitcoin/blockchain/leveldb_blockchain.hpp>

to the file src/initchain.cpp using your favourite editor such as vim.   . Then run make, sudo make install.

Now that you have sx tools installed you can use it to run all kind of bitcoin related commands.
Converting BTC to satoshi, and satoshi to BTC

$ sx btc 90000
0.00090000
$ sx satoshi 0.00090000
90000

Create an experimental wallet

sx newseed > wallet.seed
cat wallet.seed
sx wallet wallet.seed

 Convert from hexadecimal to base58

sx base58-encode CAFEBABE

See http://sx.dyne.org/  for a full list.

To be able to access a Ledger Wallet you will need: your Ledger Wallet, your PIN code and your second factor card. If one of these things is missing you won’t be able to spend bitcoin. Similar to the Ledger Wallet, Trezor has a PIN code. If the Trezor wallets gets stolen, thieves cannot misuse it.  In case of loss or theft of your Ledger Wallet, or at any time, you can restore your entire balance either on a new Ledger Wallet or on any BIP39 compatible software wallet such as Electrum. Without the PIN code and the second factor card, a thief cannot access your bitcoins.

Trezor uses a screen instead of a security card, which is of course easy for the end user. Trezor is a single-purpose computer, which stores your private keys and actively signs transactions without sending your private keys to the computer;  To run the Ledger Wallet you need a computer with an USB port, and a recent version of Google Chrome. The wallet interfaces with the computer through a Chrome application which you will need to install on your computer.  It currently does not have a screen but the Ledger Wallet will have a screen in the next version.  Both wallets are Windows, OS X and Linux friendly.  The Ledger Wallet development team is currently building support for Android;

 Read more:

• Trezor wallet:   http://www.bitcointrezor.com/
• Ledger wallet : https://www.ledgerwallet.com/

The lowest sales price being 353 $ and the highest 383 $, a difference of 30 $.   If you buy at a lower price with large amounts,  you could make profits;  You should consider where (bank or otherwise) and when the money will be delivered to you. Secondly, if you can trust the site or exchange.  Finally, you should consider when you sell or buy.

Do you sell and buy at loss? When would be the best time to sell?  It all depends on the bitcoin market price.  In October the price was 294 $,   while in August 586$. How much difference a few months can make; Because of these many uncertainties trading is not an easy task and requires skill and good prediction models, also known as trading bots.  Alternatively you just wait, buy low, sell high; What are your trading strategies? feel free to comment.