Build a Recipe Ingredient Converter - Step 13

JavaScript
1

Tell us what’s happening:

I’m not sure why this wouldn’t return the correct value- all of the processing is in the functions that I’m calling, so do I need to format the result before returning it?

Your code so far

<!-- file: index.html -->
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Recipe Ingredient Converter</title>
    <link rel="stylesheet" href="styles.css" />
  </head>
  <body>
    <main class="container">
      <h1>Recipe Ingredient Converter</h1>
      <form id="recipe-form">
        <div class="input-container">
          <label for="ingredient">Ingredient:</label>
          <input type="text" id="ingredient" required />
        </div>

        <div class="input-container">
          <label for="quantity">Quantity:</label>
          <input type="number" id="quantity" step="any" required />
        </div>

        <div class="input-container">
          <label for="unit">Unit:</label>
          <select id="unit">
            <option value="cup">Cup</option>
            <option value="gram">Gram</option>
            <option value="ounce">Ounce</option>
            <option value="teaspoon">Teaspoon</option>
          </select>
        </div>
        <div class="input-container">
          <label for="servings">Number of Servings:</label>
          <input type="number" id="servings" step="any" value="1" />
        </div>
        <button type="submit">Convert</button>
      </form>

      <section>
        <h2>Converted Ingredients</h2>
        <ul id="result-list"></ul>
      </section>
    </main>
    <script src="script.js"></script>
  </body>
</html>

/* file: styles.css */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --dark-grey: #0a0a23;
  --white: #fff;
  --light-grey: #ddd;
  --golden-yellow: #fecc4c;
  --yellow: #ffcc4c;
  --gold: #feac32;
  --orange: #ffac33;
  --dark-orange: #f89808;
}

body {
  font-family: Arial, sans-serif;
  background-color: var(--dark-grey);
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}

h1 {
  margin: 10px 0 15px;
}

.container {
  text-align: center;
  background: var(--white);
  padding: 20px;
  border-radius: 8px;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
  width: 100%;
  max-width: 600px;
}

input,
select {
  padding: 10px;
  font-size: 16px;
  margin: 5px 0;
  border: 1px solid var(--light-grey);
  border-radius: 4px;
}

button {
  font-size: 1.2rem;
  cursor: pointer;
  width: 200px;
  margin: 20px 0 30px;
  color: var(--dark-grey);
  background-color: var(--gold);
  background-image: linear-gradient(var(--golden-yellow), var(--orange));
  border-color: var(--gold);
  border-width: 3px;
}

button:hover {
  background-image: linear-gradient(var(--yellow), var(--dark-orange));
}

ul {
  list-style-type: none;
  padding: 0;
}

li {
  padding: 10px;
  border-bottom: 1px solid var(--light-grey);
  display: flex;
  justify-content: space-between;
}

/* file: script.js */
const conversionTable = {
  cup: { gram: 240, ounce: 8.0, teaspoon: 48 },
  gram: { cup: 1 / 240, ounce: 0.0353, teaspoon: 0.2 },
  ounce: { cup: 0.125, gram: 28.35, teaspoon: 6 },
  teaspoon: { cup: 1 / 48, gram: 5, ounce: 0.167 },
}

const convertQuantity = (fromUnit) => (toUnit) => (quantity) => {
  const conversionRate = conversionTable[fromUnit][toUnit];
  return quantity * conversionRate;
}

const gramsResult = convertQuantity("cup")("gram")(2);
console.log(gramsResult);

const adjustForServings = (baseQuantity) => (newServings) =>
  (baseQuantity / 1) * newServings;

const servingsResult = adjustForServings(4)(6);
console.log(servingsResult);


// User Editable Region

const processIngredient = (baseQuantity, baseUnit, newUnit, newServings) => {
  /*console.log(baseQuantity);
  console.log(baseUnit);
  console.log(newUnit);
  console.log(newServings);*/
  let adjustedServings = adjustForServings(baseQuantity)(newServings);
  console.log(adjustedServings);
  let convertedQuantity = convertQuantity(baseUnit)(newUnit)(newServings);
  return String(convertedQuantity); 
}

console.log(processIngredient(1, "gram", "cup", 4));

// User Editable Region

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Challenge Information:

Build a Recipe Ingredient Converter - Step 13
https://www.freecodecamp.org/learn/full-stack-developer/workshop-recipe-ingredient-converter/step-13

2

Hi @neat-hannah

I broke down the instructions into three steps:

  1. Your function should adjust the servings for the base quantity to the new servings,
  2. convert that adjusted quantity from the base unit into the new unit, and
  3. return the converted quantity as a fixed string with two decimal places.

Happy coding

3

I tried returning convertedQuantity.toFixed(2) to convert it to a string with 2 d.p., but apparently this is still wrong. Is there another method to convert the number to the correct format, or am I wrong in some other part of the program?

4

Should I be rounding the result or truncating it? I think this could be the source of the error, as each method will return a different result.

5

Hi @neat-hannah

Please post your updated code.

Happy coding