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1500 questions
15
votes
1 answer
What is a block hash?
When we look at this block - what does the first number
Hash: 0xfe88c94d860f01a17f961bf4bdfb6e0c6cd10d3fda5cc861e805ca1240c58553
actually mean? How is it calculated?
"Nonce" is the value that is changed during mining, but what is hash?
Matias
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15
votes
0 answers
What is the difference between "geth" and "geth --fast"?
EDIT : I hadn't see the other question but this one ain't a duplicate because I'm asking here, precisely, if the state differs and if it does, what are the implications. The answer to that question isn't present in the other question and isn't…
Cedric Martin
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15
votes
3 answers
Export Parity private key
Good afternoon all. Been searching around for an answer to this question and can't seem to find the exact solution I need.
I have an ETH account on my Parity node that I want to move to Ethereum Wallet (geth). I have the key file from Parity which…
maff1989
- 253
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15
votes
10 answers
Invalid Address Error when interacting with a smart contract with metamask
I want to call the methods with metamask of this simple contract:
contract AssetPrices {
mapping (uint => uint) public prices;
uint public data;
function EnterPrice(uint _time, uint _price){
prices[_time] = _price;
}
function…
gpanterov
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15
votes
4 answers
Can incentive be provided for non-mining Ethereum nodes?
Setting up a full-time mining rig is a tremendous resource commitment - and you either have to be all-in or go home if you want to ever actually see any return (yeah, I know - I'm ignoring syndicate/collective mining).
On the other hand, running a…
jimkberry
- 1,306
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- 11
15
votes
2 answers
What is the difference between m/44'/60'/0'/0 and m/44'/60'/0'?
When linking MyEtherWallet with a hardware wallet, there is a dropdown to select the HD derivation path. I understand that m/44'/60'/0'/0 is the default. For some reason Ledger uses m/44'/60'/0'. I'm not sure what the missing /0 means in the context…
Randomblue
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15
votes
1 answer
How are the account "pictures" used in Mist generated?
In mist, all accounts have a colourful pixelated "profile picture" used to identify them. For instance, in this screenshot from the Mist releases page, the Dogecoin Bounty DAO is given a purple profile pic. How are these generated?
Josh Stark
- 1,094
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15
votes
2 answers
Truffle migrate fails
I am using testrpc. While running truffle migrate I get the following error:
/usr/local/lib/node_modules/truffle/node_modules/truffle-contract/contract.js:671
throw new Error(this.contract_name + " has no network configuration for its…
Parthasarathy Ramanujam
- 850
- 9
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15
votes
1 answer
How to choose an account to deploy a contract in truffle
How do you select an account to deploy a contract using:
1)Metamask
2)Parity
3)some config file
rstormsf
- 4,337
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15
votes
1 answer
Solidity: How to specify a (hard-coded) address as a literal
I am defining a contract and I want to ensure a particular member variable can only be modified by me. So, specifically I want to ensure that if someone else deploys one of my contracts, then they will not be able to modify this variable.
To do this…
ianinini
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15
votes
3 answers
Mining with geth on private network hangs indefinitely
I've got a private test network running as per this article. In particular my difficulty is set to 0x400; the entire genesis file I'm using can be seen here.
Mining with geth does not seem to work at all.
Here's what I've tried to do. First a…
jtobin
- 433
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15
votes
3 answers
How to parse blocks with Python?
I'm building a basic analytics framework for the Ethereum blockchain. As a first step I need to extract the data and I'd like to do this in Python. I've been using Geth as a client on OSX and so, as far as I understand, the blockchain is stored…
antianticamper
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15
votes
4 answers
What is PoWhash?
When I mine, I get something that says:
miner 22:09:05|main Mining on PoWhash #45feeecf… : 6761650 H/s = 3407872 hashes / 0.504 s
What does PoWhash mean? I'm assuming that the #45feeecf… is a partial hash of the current block I'm mining?
Alec
- 253
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15
votes
2 answers
Is it impossible to use an array of strings as the argument to solidity function?
If I try to define a function using an array of strings as an argument, solc gives me the following error:
Error: Internal type is not allowed for public or external functions.
function test(string[] x){}
^--------^
This works…
gellej
- 480
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15
votes
4 answers
How to obtain all transaction of a contract?
I'm trying to obtain all the transactions of a contract, but in all cases I only obtained [] or undefined.
I'm following this posts:
Common useful JavaScript snippets for geth
web3 filter option not working
And I read others posts too, but i can't…
Gawey
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