Shrortest Distnace 🛰, clean code 👨🏻‍💻, TCP 🖧, ML 🤖| Techletter #73

How to calculate the shortest distance between two places?

To calculate the shortest distance between two places, we use the haversine formula. It is a mathematical formula used to calculate the great-circle distance between two points on a sphere. Here, we get the shortest straight-line difference and is not the exact on-road distance.

function haversine_distance(lat1, lon1, lat2, lon2) {
  const R = 6371; // Radius of the Earth in kilometers

  // Convert latitudes and longitudes to radians
  const lat1_rad = lat1 * Math.PI / 180;
  const lon1_rad = lon1 * Math.PI / 180;
  const lat2_rad = lat2 * Math.PI / 180;
  const lon2_rad = lon2 * Math.PI / 180;

  // Calculate the differences in latitude and longitude
  const dlat = lat2_rad - lat1_rad;
  const dlon = lon2_rad - lon1_rad;

  // Calculate the Haversine distance
  const a = Math.sin(dlat/2)**2 + Math.cos(lat1_rad) * Math.cos(lat2_rad) * Math.sin(dlon/2)**2;
  const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));
  const d = R * c;

  return d;
}

// Example usage:
const lat1 = 12.91733;
const lon1 = 77.63148;
const lat2 = 12.92567;
const lon2 = 77.63672;

const distance = haversine_distance(lat1, lon1, lat2, lon2);
console.log({ distance });
console.log(`The distance between the two points is ${distance.toFixed(2)} kilometers.`);

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isBooleanTooLongAndComplex

Have you ever come across an if statement that is too long? If you want it to be more readable and meaningful, here is how it can be done.

// Decide whether this pizza is fantastic.

if ((!pepperoniService.empty() || sausages.size() > 0)

    && (useOnionFlag.get() || hasMushroom(ENOKI, PORTOBELLO)) && hasCheese()) {

  ...

}

The above steps can be broken down into multiple booleans like below

boolean isPizzaFantastic() {

  if (!hasCheese()) {

    return false;

  }

  if (pepperoniService.empty() && sausages.size() == 0) {

    return false;

  }

  return useOnionFlag.get() || hasMushroom(ENOKI, PORTOBELLO);
}

Link to the original article

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What is a TCP?

Transmission Control Protocol(TCP) is a standard that defines how to establish and maintain a network conversation by which applications can exchange data.

Key characteristics of TCP include:

• Connection-oriented: The TCP establishes a connection between the client and the server before data can be exchanged.

• Reliable data transfer: It provides reliable, ordered, and error-checked delivery of data by breaking it into packets, numbering them, and waiting for acknowledgments from the receiver.

• Flow control: It manages the flow of data to prevent the sender from overwhelming the receiver with too many packets

• Layered architecture: It resides in the transport layer of the OSI model, providing host-to-host connectivity

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Lists, tuples, and dictionaries in Python

List: The Python list is just like a dynamic-sized array.

variable_name = [item1, item2, item3, item4]

Tuple: is used to store multiple values separated by a comma in an ordered manner. The tuple is immutable, which means once it is created it cannot be modified.

variable_name = (item1, item2, item3)

Dictionary:

A dictionary is an unordered collection of various data types used for storing data values like maps. It can store key-value pairs.

variable_name = { k1: v1, k2: v2 }

The dictionaries are also known as associative memories or associative arrays. The keys in the dictionary must be unique.

Machine Learning Section

This week in Machine learning I did explore a few things. Here are a few points.

• 2 types of learning: Supervised learning and unsupervised learning.

• In supervised learning, we have two kinds: classification and regression.

• Machine learning is nothing but turning data information.

• Features are also called attributes.

• In unsupervised learning, we have two kinds clustering and density estimation.

• Steps while building an ML application:

  • Collect data

  • Prepare the input data

  • Analyze the input data

  • Train the algorithm

  • Test the algorithm

  • Use the algorithm

What is a machine learning model?

A machine learning model is a program that is trained to recognize patterns in data and make decisions or predictions without being explicitly programmed.