Trending questions in Blockchain

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Python Double hash SHA256

You can get the given hash by ...READ MORE

Aug 29, 2018 in Blockchain by slayer
• 29,370 points
3,146 views
0 votes
1 answer

Web3 1.0: What does `web3.eth.call(tx)` return for a contract creation?

The returned bytestring is the deployedBytecode of the contract, ...READ MORE

Sep 17, 2018 in Blockchain by digger
• 26,740 points
2,320 views
0 votes
1 answer

How to achieve simple OOP in Solidity?

contract A { uint public ...READ MORE

Sep 27, 2018 in Blockchain by slayer
• 29,370 points
1,881 views
0 votes
1 answer

How to solve “ltdl.h: No such file or directory” error?

It seems like you are missing header ...READ MORE

Jul 26, 2018 in Blockchain by slayer
• 29,370 points
4,588 views
0 votes
1 answer

Problem while compiling BitcoinJS for browser

The problem iss that you are using browserify wrong ...READ MORE

Aug 30, 2018 in Blockchain by digger
• 26,740 points
3,071 views
0 votes
1 answer

What Regex to use to identify a Block Hash?

Blockhashes are always 64 characters in length. You ...READ MORE

Aug 28, 2018 in Blockchain by digger
• 26,740 points
3,146 views
0 votes
1 answer

How to run Meteor insert within a Fiber?

Just replace events.watch(function(error, event) { ... }); with events.watch(Meteor.bindEnvironment(function(error, event) ...READ MORE

Sep 28, 2018 in Blockchain by slayer
• 29,370 points
1,771 views
0 votes
1 answer

Trying to understand nbits value from stratum protocol

You are right, nbits is current network difficulty. Difficulty encoding ...READ MORE

Sep 3, 2018 in Blockchain by Perry
• 17,100 points
2,845 views
0 votes
1 answer

How to extend Composer rest Server ?

 It looks like you want to query ...READ MORE

Sep 20, 2018 in Blockchain by Perry
• 17,100 points
2,094 views
0 votes
1 answer

How to access bitcoin Daemon from other services?

You don't need all these things to ...READ MORE

Aug 29, 2018 in Blockchain by digger
• 26,740 points
3,044 views
0 votes
1 answer

Store contract results tag in a variable

then() takes a function as argument that is ...READ MORE

Oct 9, 2018 in Blockchain by Omkar
• 69,180 points
1,265 views
0 votes
2 answers

How to read CGMiner output?

the only thing that made it work ...READ MORE

Sep 17, 2018 in Blockchain by Ruby
2,283 views
0 votes
1 answer

Getting error during “truffle migrate” for an ethereum contract on testrpc

Can you just try to give network ...READ MORE

Sep 27, 2018 in Blockchain by slayer
• 29,370 points
1,760 views
0 votes
2 answers

Trying to issue tokens on testnet with python API

By looking at - documentation here I think you ...READ MORE

Sep 17, 2018 in Blockchain by Khush
2,136 views
0 votes
1 answer

Sawtooth Javascript SDK "Batchlist rejected" error

What you can do is use intkey-client to the ...READ MORE

Sep 19, 2018 in Blockchain by digger
• 26,740 points
2,085 views
0 votes
1 answer

Public key encoding changes

You are printing the memory address of ...READ MORE

Sep 19, 2018 in Blockchain by Christine
• 15,750 points
2,078 views
+1 vote
1 answer

Coinbase API: Get transaction fees

The Coinbase "fee" is the difference between ...READ MORE

Aug 23, 2018 in Blockchain by digger
• 26,740 points
3,202 views
0 votes
1 answer

ERRO : Error trying to connect to local peer: grpc: timed out trying to connect

You need to use the correct port ...READ MORE

Sep 17, 2018 in Blockchain by slayer
• 29,370 points
2,155 views
0 votes
1 answer

Can we set a list of discovery nodes in Hyperledger fabric?

New nodes doesn't depend on a single ...READ MORE

Sep 19, 2018 in Blockchain by Christine
• 15,750 points
2,066 views
0 votes
2 answers

VBA code leads to #value! in cell but works in immediate box

Function GetPrice(strTicker As String, Optional dtDate As ...READ MORE

Sep 10, 2018 in Blockchain by Garry
2,402 views
+1 vote
2 answers

HyperLedger Fabric Java SDK - Wrinting the ChainCode Sample in Java

To get started developing Java chaincode Ensure you ...READ MORE

Aug 3, 2018 in Blockchain by Omkar
• 69,180 points
6,619 views
0 votes
1 answer

blockchain/service-my-wallet-v3 - Connection refused

Hey, if you have installed blockchain/service-my-wallet properly, ...READ MORE

Sep 18, 2018 in Blockchain by slayer
• 29,370 points
2,079 views
0 votes
1 answer

What do I import for SHA encryption in Node.js?

var sha = require('sha.js'); //... getHash() { ...READ MORE

Sep 21, 2018 in Blockchain by digger
• 26,740 points
1,944 views
0 votes
1 answer

Nodejs: How to pass user form data into defined class

This should do your work: // select the ...READ MORE

Sep 19, 2018 in Blockchain by digger
• 26,740 points
2,025 views
0 votes
1 answer

What's the difference between ethereum and chain?

Ethereum is an open source blockchain platform ...READ MORE

Sep 12, 2018 in Blockchain by Perry
• 17,100 points
2,315 views
0 votes
2 answers

PHP: json_decode - reading category names

<?php function findHighestBid() { $result = ...READ MORE

Sep 7, 2018 in Blockchain by Shotgun
2,490 views
0 votes
1 answer

PHP Bitcoin validate from form

isValid($addr, $version) $addr: A bitcoin address $version: The ...READ MORE

Sep 3, 2018 in Blockchain by slayer
• 29,370 points
2,691 views
0 votes
1 answer

how loop through a JSON Array of bitcoin transaction data

for($i=0; $i<count($result['out']); $i++) { echo ...READ MORE

Sep 21, 2018 in Blockchain by slayer
• 29,370 points
1,910 views
0 votes
1 answer

How to compute SHA256 hash for bitcoin header

header_hex = "02000000aaf8ab82362344f49083ee4edef795362cf135293564c4070000000000000000c009bb6222e9bc4cdb8f26b2e8a2f8d163509691a4038fa692abf9a474c9b21476800755c02e17181fe6c1c3" # Decode header hex into ...READ MORE

Aug 31, 2018 in Blockchain by digger
• 26,740 points
2,818 views
0 votes
1 answer

pybitcointools pushtx TypeError: expected string or buffer

From the looks of it, you need ...READ MORE

Sep 6, 2018 in Blockchain by digger
• 26,740 points
2,559 views
0 votes
1 answer

How are the ethers sent to smart contract in the IBM example?

They are in magical variable msg. The function ...READ MORE

Sep 28, 2018 in Blockchain by digger
• 26,740 points
1,590 views
+2 votes
1 answer

What is Bitcoin Powered Electrical Outlet?

Bitcoin powered electrical outlet is nothing but ...READ MORE

Sep 20, 2018 in Blockchain by Bhaskar
1,848 views
+1 vote
1 answer

Is there a way to send funds from a specific bitcoin address in a wallet?

I'll answer my own question, It was unbelievably ...READ MORE

Sep 3, 2018 in Blockchain by Perry
• 17,100 points
2,611 views
0 votes
1 answer

How to use ethereum contract's state changing method in javascript?

You'll find that the message is indeed ...READ MORE

Sep 11, 2018 in Blockchain by Christine
• 15,750 points
2,303 views
0 votes
1 answer

How to get all address and send ethers in solidity using a loop?

I found a similar code somewhere: contract  Holders{ uint ...READ MORE

Jul 31, 2018 in Blockchain by digger
• 26,740 points
4,100 views
0 votes
1 answer

Not able to send Ethereum transaction

Hey, Change this line: await crowdsale.sendTransaction({value, from: buyer, gas: ...READ MORE

Sep 24, 2018 in Blockchain by slayer
• 29,370 points
1,716 views
0 votes
1 answer

How do I withdraw the balance from a contract on Ethereum test blockchain?

Your need to improvise your code a ...READ MORE

Aug 3, 2018 in Blockchain by Perry
• 17,100 points
3,960 views
+1 vote
1 answer

Node.js blockchain bitcoin api

The callback URL should be the one ...READ MORE

Sep 10, 2018 in Blockchain by slayer
• 29,370 points
2,276 views
0 votes
1 answer

How to retrieve data from a block to a blockchain?

web3.eth.getTransaction(txHash) will returns transaction details like blockHash, transactionIndex, ...READ MORE

Jun 27, 2018 in Blockchain by Perry
• 17,100 points
5,580 views
0 votes
1 answer

How to create a private bitcoin network using bitcore?

I think you need to add your ...READ MORE

Sep 6, 2018 in Blockchain by slayer
• 29,370 points
2,471 views
0 votes
1 answer

How to use std::iterator with basic type uint8_t*?

std::reverse_iterator takes the original iterator type as ...READ MORE

Aug 24, 2018 in Blockchain by slayer
• 29,370 points
3,034 views
0 votes
1 answer

Required parameter missing: account error

You need to swap out the place ...READ MORE

Aug 30, 2018 in Blockchain by slayer
• 29,370 points
2,767 views
0 votes
1 answer

How to create raw transaction using web3swift?

var options = Web3Options.defaultOptions() options.gasLimit = BigUInt(21000) options.from = ...READ MORE

Sep 17, 2018 in Blockchain by slayer
• 29,370 points
1,990 views
0 votes
1 answer

How to “unrecognized import path error” while using go for hyperledger fabric?

The solution to this problem is as ...READ MORE

Jul 27, 2018 in Blockchain by slayer
• 29,370 points
4,235 views
0 votes
1 answer

ethminer failed to submit hashrate

The pool you are linking with the -F flag ...READ MORE

Sep 24, 2018 in Blockchain by digger
• 26,740 points
1,680 views
0 votes
1 answer

How connect library to smart contract from external resources?

pragma solidity ^0.4.0; import "github.com/OpenZeppelin/zeppelin-solidity/contracts/math/SafeMath.sol"; contract MathExtended { ...READ MORE

Sep 26, 2018 in Blockchain by digger
• 26,740 points
1,590 views
0 votes
1 answer

obfuscating and deobfuscating a string in JavaScript

You can use btoa() and atob(). btoa() is like base64_encode() and atob() like base64_decode(). Here is an example: btoa('Some ...READ MORE

Aug 23, 2018 in Blockchain by slayer
• 29,370 points
3,051 views
0 votes
1 answer

How to get genesis block value at new bitcoin source?

chainparams.cpp contains a line of code that ...READ MORE

Sep 4, 2018 in Blockchain by digger
• 26,740 points
2,522 views
0 votes
1 answer

How to handle Overlapping of array objects in node js

Try this code, may be it works for ...READ MORE

Sep 18, 2018 in Blockchain by digger
• 26,740 points
1,915 views
0 votes
1 answer

Syntax Error running on Python

You are missing the closing parenthesis: hashlib.sha256(self.index + ...READ MORE

Sep 21, 2018 in Blockchain by digger
• 26,740 points
1,781 views