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Showing posts from September, 2020

What are basic string methods in Python?

 What are basic string methods in Python? In Python, strings are immutable.This means that they can not be modified.So if we wanted to repair a typo in string,we can't simply modify the incorrect character. We would need to create a replacement string with typo corrected.We can also assign a replacement value to the variable holding our string. If we aren't sure what the index of our type is, we will use the string method index to locate it and return the index. lets say we've the string"lions tigers and bears" within the variable animals.We can locate the index that contains the letter g using animals index("9"), which can return the index; during this case 8. We can also use sub strings to locate the index where the sub string begins, animal index("bears") would return 17, since that is the start of the sub string.If there's quite one match for a sub string, the index method will return the primary match. If

String indexing and Slicing in Python

 String indexing and Slicing in Python String indexing allow us to access individual characters in a string. We can do this by using square brackets and the location,or index,of the character you want to access. It's important to remember that Python starts indexes at 0.So to access the first character in a string,you would use the index[0]. If we try to access an index that's larger than the length of your string,you'll get and Index Error. This is because you're trying to access something that doesn't exist. We can also access indexes from the end of the string going towards the start of the string by using negative values. The index[-1] would access the last character of the string,and the index[-2] would access the second-to-last character. We can also access a portion of a string,called a slice or a sub string.This allows you to access multiple characters of a string.  We can do this by creating a range,using a colon as separator between the start and end of t

What is the Transaction nonce?

 What is the Transaction nonce? nonce: A scalar value adequate to the amount of transactions sent from this address or, within the case of the accounts with associated code, the amount of contact-creations made by this account. For EOA This number represents the amount of confirm transactions sent from the account's address. For contract Address: The nonce is that the number of contracts created by the account. It's important to notice that the utilization of nonce is really vital for an account-base protocol, in contrast to the "unspent transaction output" (UTXO) mechanism of the Bitcoin protocol. What does it matter? This value prevents double-spending, because the nonce will always specify the order of transactions.If a double-spend does occur, it's typically thanks to the subsequent process. A transaction is shipped to at least one party. They await it to register. Something is collected from this first transaction

Implicit vs Explicit Conversion

 Implicit vs Explicit Conversion Description There are numerous types of data in Python programming. We must know their inter-conversion. How to covert these data types using inbuilt functions in Python i.e. Type Casting ? Performing type conversions is one of the many things we can do with Python's functions. Let's first discuss the Python data types in brief before proceeding towards topic. Integers Python gives any number without a prefix as an integer. The values of integer may be as long as we want . These are digits too in Python. We can't have forever long integers if we have a supercomputer. These numbers also contain decimal digits. Floating Point Numbers For splitting the fractional digits and the integer floats are numbers that are written with a decimal point. Example of floating point numbers are 5.2, 8.17,3.31 etc. Complex Numbers In Python, complex numbers display this format :(the real part + the imaginary part). Examples of complex numbers are (4+1i), (6-4

Wallet Technology Overview

 Wallet Technology Overview Ethereum wallet may be a key chain containing pairs of personal and public keys,Ethereum wallet doesn't contain ether or tokens.From these keys they control the ether or tokens. User sign transactions with the private keys,there by proving they own the ether.The ether is stored on the blockchain. Types of Wallet There are two primary sorts of wallets, distinguished by whether the keys they contain are associated with one another or not. 1.Nondeterministic wallet (HD Wallet) Each key's independantally generated from a special random number. The keys aren't associated with one another . Also referred to as JBOK (Just a bunch of keys) wallet. 2.Deterministic wallet All the keys are derived from one passkey ,known as Seed. Keys are associated with one another . It are often generated again from original seed the foremost common method is free-like-structure.Also referred to as HD(H

Public Key Cryptography and Cryptocurrency

 Public Key Cryptography and Cryptocurrency What is Cryptography? it's the study of techniques for secure communication within the presence of third parties called adversaries. In simple words it's about constructing and analyzing protocols for prevent third parties from reading private messages. Current cryptography is especially supported mathematical theory and computing practice. What is Cryptocurrency? it's a digital asset designed to figure as a medium of exchange wherein individual coin ownership records are stored during a ledger existing during a sort of computerized data base using strong cryptography to secure transaction records, to regulate the creation of additional coins, and to verify the transfer of coin ownership. Public Key Cryptography and Cryptocurrency In Ethereum, we use public key cryptography(also referred to as asymmetric cryptography) to make the public-private key pair. Together they represent on Ether

Addresses and Keys

 Addresses and Keys Addresses One of Ethereum's foundational technologies is cryptography. There are two sorts of Accounts. Externally owned Accounts (EOA) Contract Account Ownership of ether by EOA is established through Digital private keys. Ethereum addresses, and  Digital signatures An externally owned account can send messages to other externally owned accounts OR to other contract accounts by creating and signing a transaction using its private key. Unlikely externally owned accounts,contract accounts can't initiate new transactions on their own. KEYS Private keys aren't used directly in Ethereum system. Account addresses are derived directly from private keys. Private key uniquely determines one Ethereum address,also referred to as an account. Access and control of funds is achieved with digital signature. Ethereum transactions require a legitimate digital signature to be included within the blockchain. Anyone with a replica o

Running Ethereum client and test nets

 Running Ethereum client and test nets Ethereum local block chain Advantage No syncing and almost no data on disk;you mine  the primary  block yourself. No  got to  obtain test ether;you "award" yourself mining rewards  that you simply  can use for testing. No other users,just you. No other contracts,just  those  you deploy after you launch it. Disadvantage Having no other users  means  it doesn't behave  an equivalent  as a public block chain. No miners  aside from  you  means  mining is more predictable;therefore,you can't test some scenarios that occur on a public block chain. Having no other contracts means  you've got  to deploy everything  you would like  to check  ,including dependencies and contract libraries. You can't recreate  a number of  the general public  contracts and their dependencies  to check  some scenarios (e.g; the DAO contracts). Maximum requirements CPU with 2+ cores At least 80GB free  space for storing 4 GB RAM minimum with an SSD,8G

Remote clients------Test network

 Remote clients------Test network   Description Remote clients doesn't store an area copy of the blockchain or validate blocks and transactions.   They're wallet and may create and broadcast transactions.   They will be wont to hook up with existing networks , such as; Own Full Node, Public Blockchain (Mainnet) Testnet or Private (local) blockchain The term "remote client" and "wallet" are used interchangeably, through there are some differences.Usually, a foreign client offers an API(such because the web3.js API) additionally to the transaction functionality of a wallet.           Example Meta Mask and Jaxx. ETH Remote client Vs BTC Light node Don't confuse the concept of a foreign wallet in Ethereum thereupon of a light-weight client(which is analogous to a Simplified Payment Verification client in Bitcoin. Light clients validate block headers and use Merkle proofs to validate the inclusion of transactions wi

Ethereum client

 Ethereum client     An Ethereum client may be a software application that implements the Ethereum specification. Ethereum is defined by a proper specification called the "Yellow paper". Different Ethereum clients inter operate if they suits the reference specification and therefore the standardized communications protocols. This yellow paper, additionally to varied Ethereum Improvement Proposals (EIP), defines the quality behavior of an Ethereum client. The yellow paper is periodically updated as major changes are made to Ethereum. Benefits of specification Vs Implementation Built on specification proven itself to be a superb way of defending against attacks on the network,because exploitation of a specific client's implementation strategy simply hassles the developers while they patch the exploit,while other clients keep the network running almost unaffected. Ethereum Network Currently, there are six main implementations of the Ethereum

Some good starter Wallets

Some good starter Wallets Bit coin wallet A wallet stores  the knowledge  necessary to transact but coins. Types of wallets are: Desktop Bit coin OT,Multi Bit,Armony,Electrum Mobile Bit coin Wallet,Mycelium,Blockchain,coin base Cloud Coin base,Blockchain Paper wallet Hardware wallet Bit coin client soft wares Reference client(Bit coin Core) Contains a wallet,Miner,full block chain data base,and network routing node on the bit coin P2P network. 2. Full Blockchain Node Contains a full Block chain data base, and network routing node on the bit coin P2P network. 3. Lightweight(SPV) wallet Contains a wallet and a network node on the bit coin P2P protocol, without a blockchain Bit coin Address Bit coin address generated by wallet  isn't  known to bit coin network  neither is  it registered with any bit coin system. Bit coin address  is just  variety  that corresponds to a key  that you simply  can use  to regulate  access to the funds. Until  the instant  this address is referenced  be

Ethereum currency unit and Wallets

 Ethereum currency unit and Wallets  Description Ethereum's currency unit  is named  ether. It identified as "ETH" or with the symbol ≊(From the greek letter "XI" or, less often,🔷. For example: 1 ether,or 1 ETH, ≊ or 🔷1. Ether smallest unit = WEI Ether is subdivided into smaller units wei. One ether is 1 quin trillion wei (10 18 or 1000,000,00000,000,0000) Ethereum  may be a  system,ether  may be a  currency. When you transact 1 ether,the transaction encodes 1000,000,000,000,000,000 wei  because the  value. Ethereum wallets Types of Wallets Mobile Wallets, Desktop Wallet,and Web based wallet, Generally  the foremost  popular a wallet application is, the more trust worthy  it's  likely to be. It is good practice to avoid "putting all your egss in one basket" and have your Ethereum accounts spread across  a few  of wallets. Current scenario Ethereum is currently developing and  getting to  implement a series of upgrades called Ethereum 2.0 . Cur