Units, Dimensions, Scale, and Normalization

/**
 * Fintech Math Bootcamp · Lesson 009 of 120
 * Units, Dimensions, Scale, and Normalization
 * Module 01: Mathematical Language and Quantitative Reasoning
 *
 * Scenario: Cents, currencies, and rates in the same pipeline
 * Rule:     10,000 cents ÷ 100 = 100 currency units
 *
 * Try it:   Does multiplying all prices by 100 change a simple return?
 *
 * Lesson article: https://thefintechbuilder.com/financial-mathematics-statistics-and-data-foundations/mathematical-language-and-quantitative-reasoning/units-dimensions-scale-and-normalization/
 * Free course:    https://courses.thefintechbuilder.com
 * Synthetic teaching example, not financial advice or a production library.
 */

export function lesson009() {
  const cents = 10000;
  const units = cents / 100;
  const ratePerYear = 0.05;
  const years = 2;
  const interest = units * ratePerYear * years;
  const result = {units, interest};
  return result;
}

export const checkedResult = {"units":100,"interest":10};

// Run this file directly: npx tsx lessons/01-mathematical-language-and-quantitative-reasoning/009-units-dimensions-scale-and-normalization.ts
if (process.argv[1] && import.meta.url.endsWith(process.argv[1].replace(/\\/g, "/").split("/").pop()!)) {
  console.log(JSON.stringify(lesson009(), null, 2));
}

"""
Fintech Math Bootcamp · Lesson 009 of 120
Units, Dimensions, Scale, and Normalization
Module 01: Mathematical Language and Quantitative Reasoning

Scenario: Cents, currencies, and rates in the same pipeline
Rule:     10,000 cents ÷ 100 = 100 currency units

Try it:   Does multiplying all prices by 100 change a simple return?

Lesson article: https://thefintechbuilder.com/financial-mathematics-statistics-and-data-foundations/mathematical-language-and-quantitative-reasoning/units-dimensions-scale-and-normalization/
Free course:    https://courses.thefintechbuilder.com
Synthetic teaching example, not financial advice or a production library.

Run it: python main.py
"""

import json


def lesson009() -> dict:
    cents = 10000
    units = cents / 100
    rate_per_year = 0.05
    years = 2
    interest = units * rate_per_year * years
    result = {"units": units, "interest": interest}
    return result


if __name__ == "__main__":
    print(json.dumps(lesson009(), indent=2))

/**
 * Fintech Math Bootcamp · Lesson 009 of 120
 * Units, Dimensions, Scale, and Normalization
 * Module 01: Mathematical Language and Quantitative Reasoning
 *
 * Scenario: Cents, currencies, and rates in the same pipeline
 * Rule:     10,000 cents ÷ 100 = 100 currency units
 *
 * Try it:   Does multiplying all prices by 100 change a simple return?
 *
 * Lesson article: https://thefintechbuilder.com/financial-mathematics-statistics-and-data-foundations/mathematical-language-and-quantitative-reasoning/units-dimensions-scale-and-normalization/
 * Free course:    https://courses.thefintechbuilder.com
 * Synthetic teaching example, not financial advice or a production library.
 *
 * Run it: javac Main.java && java Main
 */

public class Main {
    static final class ConvertedInterest {
        final double units;
        final double interest;

        ConvertedInterest(double units, double interest) {
            this.units = units;
            this.interest = interest;
        }
    }

    static ConvertedInterest lesson009() {
        double cents = 10000;
        double units = cents / 100;
        double ratePerYear = 0.05;
        double years = 2;
        double interest = units * ratePerYear * years;
        ConvertedInterest result = new ConvertedInterest(units, interest);
        return result;
    }

    public static void main(String[] args) {
        ConvertedInterest result = lesson009();
        System.out.println(object("units", num(result.units), "interest", num(result.interest)));
    }

    // Formats a double the way JSON.stringify does: whole numbers without ".0", null for NaN or infinity.
    static String num(double x) {
        if (Double.isNaN(x) || Double.isInfinite(x)) return "null";
        if (x == Math.rint(x) && Math.abs(x) < 1e15) return String.valueOf((long) x);
        return String.valueOf(x);
    }

    static String quote(String text) {
        return "\"" + text.replace("\\", "\\\\").replace("\"", "\\\"") + "\"";
    }

    // Indents an already formatted JSON value by one level.
    static String nested(String json) {
        return json.replace("\n", "\n  ");
    }

    static String object(String... keysAndValues) {
        if (keysAndValues.length == 0) return "{}";
        StringBuilder out = new StringBuilder("{");
        for (int i = 0; i < keysAndValues.length; i += 2) {
            out.append(i == 0 ? "\n  " : ",\n  ")
               .append(quote(keysAndValues[i])).append(": ").append(nested(keysAndValues[i + 1]));
        }
        return out.append("\n}").toString();
    }
}

// Fintech Math Bootcamp · Lesson 009 of 120
// Units, Dimensions, Scale, and Normalization
// Module 01: Mathematical Language and Quantitative Reasoning
//
// Scenario: Cents, currencies, and rates in the same pipeline
// Rule:     10,000 cents ÷ 100 = 100 currency units
//
// Try it:   Does multiplying all prices by 100 change a simple return?
//
// Lesson article: https://thefintechbuilder.com/financial-mathematics-statistics-and-data-foundations/mathematical-language-and-quantitative-reasoning/units-dimensions-scale-and-normalization/
// Free course:    https://courses.thefintechbuilder.com
// Synthetic teaching example, not financial advice or a production library.
//
// Run it: go run main.go

package main

import (
	"encoding/json"
	"fmt"
)

type ConvertedInterest struct {
	Units    float64 `json:"units"`
	Interest float64 `json:"interest"`
}

func lesson009() ConvertedInterest {
	cents := 10000.0
	units := cents / 100
	ratePerYear := 0.05
	years := 2.0
	interest := units * ratePerYear * years
	result := ConvertedInterest{Units: units, Interest: interest}
	return result
}

func main() {
	printJSON(lesson009())
}

// printJSON prints a value as JSON indented with two spaces, like JSON.stringify(value, null, 2).
func printJSON(value any) {
	out, err := json.MarshalIndent(value, "", "  ")
	if err != nil {
		panic(err)
	}
	fmt.Println(string(out))
}

/**
 * Fintech Math Bootcamp · Lesson 009 of 120
 * Units, Dimensions, Scale, and Normalization
 * Module 01: Mathematical Language and Quantitative Reasoning
 *
 * Scenario: Cents, currencies, and rates in the same pipeline
 * Rule:     10,000 cents ÷ 100 = 100 currency units
 *
 * Try it:   Does multiplying all prices by 100 change a simple return?
 *
 * Lesson article: https://thefintechbuilder.com/financial-mathematics-statistics-and-data-foundations/mathematical-language-and-quantitative-reasoning/units-dimensions-scale-and-normalization/
 * Free course:    https://courses.thefintechbuilder.com
 * Synthetic teaching example, not financial advice or a production library.
 *
 * Run it: g++ -std=c++17 -o main main.cpp && ./main
 */

#include <charconv>
#include <cmath>
#include <iostream>
#include <string>
#include <utility>
#include <vector>

// Formats a double the way JSON.stringify does: shortest round-trip form, null for NaN or infinity.
std::string num(double x) {
    if (!std::isfinite(x)) return "null";
    char buffer[32];
    auto [end, error] = std::to_chars(buffer, buffer + sizeof buffer, x);
    (void)error;
    return std::string(buffer, end);
}

std::string quote(const std::string& text) {
    std::string out = "\"";
    for (char c : text) {
        if (c == '"' || c == '\\') out += '\\';
        out += c;
    }
    return out + "\"";
}

// Indents an already formatted JSON value by one level.
std::string nested(const std::string& json) {
    std::string out;
    for (char c : json) {
        out += c;
        if (c == '\n') out += "  ";
    }
    return out;
}

std::string object(const std::vector<std::pair<std::string, std::string>>& fields) {
    if (fields.empty()) return "{}";
    std::string out = "{";
    for (std::size_t i = 0; i < fields.size(); ++i) {
        out += i == 0 ? "\n  " : ",\n  ";
        out += quote(fields[i].first) + ": " + nested(fields[i].second);
    }
    return out + "\n}";
}

struct ConvertedInterest {
    double units;
    double interest;
};

ConvertedInterest lesson009() {
    const double cents = 10000;
    const double units = cents / 100;
    const double ratePerYear = 0.05;
    const double years = 2;
    const double interest = units * ratePerYear * years;
    const ConvertedInterest result{units, interest};
    return result;
}

int main() {
    const ConvertedInterest result = lesson009();
    std::cout << object({{"units", num(result.units)}, {"interest", num(result.interest)}}) << "\n";
}

//! Fintech Math Bootcamp · Lesson 009 of 120
//! Units, Dimensions, Scale, and Normalization
//! Module 01: Mathematical Language and Quantitative Reasoning
//!
//! Scenario: Cents, currencies, and rates in the same pipeline
//! Rule:     10,000 cents ÷ 100 = 100 currency units
//!
//! Try it:   Does multiplying all prices by 100 change a simple return?
//!
//! Lesson article: https://thefintechbuilder.com/financial-mathematics-statistics-and-data-foundations/mathematical-language-and-quantitative-reasoning/units-dimensions-scale-and-normalization/
//! Free course:    https://courses.thefintechbuilder.com
//! Synthetic teaching example, not financial advice or a production library.
//!
//! Run it: rustc main.rs && ./main

struct ConvertedInterest {
    units: f64,
    interest: f64,
}

fn lesson009() -> ConvertedInterest {
    let cents = 10000.0;
    let units = cents / 100.0;
    let rate_per_year = 0.05;
    let years = 2.0;
    let interest = units * rate_per_year * years;
    let result = ConvertedInterest { units, interest };
    result
}

fn main() {
    let result = lesson009();
    println!(
        "{}",
        object(&[("units", num(result.units)), ("interest", num(result.interest))])
    );
}

/// Formats a number the way JSON.stringify does: shortest round-trip form, null for NaN or infinity.
fn num(x: f64) -> String {
    if x.is_finite() {
        format!("{}", x)
    } else {
        "null".to_string()
    }
}

fn quote(text: &str) -> String {
    format!("\"{}\"", text.replace('\\', "\\\\").replace('"', "\\\""))
}

/// Indents an already formatted JSON value by one level.
fn nested(json: &str) -> String {
    json.replace('\n', "\n  ")
}

fn object(fields: &[(&str, String)]) -> String {
    if fields.is_empty() {
        return "{}".to_string();
    }
    let lines: Vec<String> = fields
        .iter()
        .map(|(key, value)| format!("  {}: {}", quote(key), nested(value)))
        .collect();
    format!("{{\n{}\n}}", lines.join(",\n"))
}

/**
 * Fintech Math Bootcamp · Lesson 009 of 120
 * Units, Dimensions, Scale, and Normalization
 * Module 01: Mathematical Language and Quantitative Reasoning
 *
 * Scenario: Cents, currencies, and rates in the same pipeline
 * Rule:     10,000 cents ÷ 100 = 100 currency units
 *
 * Try it:   Does multiplying all prices by 100 change a simple return?
 *
 * Lesson article: https://thefintechbuilder.com/financial-mathematics-statistics-and-data-foundations/mathematical-language-and-quantitative-reasoning/units-dimensions-scale-and-normalization/
 * Free course:    https://courses.thefintechbuilder.com
 * Synthetic teaching example, not financial advice or a production library.
 *
 * Run it: dotnet run  (inside a console project that holds this Program.cs)
 */

using System.Text.Json;

var jsonOptions = new JsonSerializerOptions { WriteIndented = true, PropertyNamingPolicy = JsonNamingPolicy.CamelCase };
Console.WriteLine(JsonSerializer.Serialize(Lesson009(), jsonOptions));

static ConvertedInterest Lesson009()
{
    const double cents = 10000;
    const double units = cents / 100;
    const double ratePerYear = 0.05;
    const double years = 2;
    const double interest = units * ratePerYear * years;
    var result = new ConvertedInterest(units, interest);
    return result;
}

record ConvertedInterest(double Units, double Interest);