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## Manipulate Values
5 years ago
### Instructions
Go buy groceries!!!
You have a grocery cart with some items you need.
The items will have a `key` being the name and a `value` that is the amount in grams.
Create 3 functions that works like the `.filter`, `.map` and `.reduce` array method but for the values of your grocery cart.
5 years ago
- `filterValues` filters the values of your grocery cart.
- `mapValues` changes the values of your grocery cart.
For the above function the callback function should accepts only the element in the arguments, this being the current element being processed.
- `reduceValues` that will reduce your grocery cart. The callback function should accepts only the **accumulated value** and the **current value**.
### Examples
```js
const nutrients = { carbohydrates: 12, protein: 20, fat: 5 }
console.log(filterValues(nutrients, (nutrient) => nutrient <= 12))
// output :
// { carbohydrates: 12, fat: 5 }
console.log(mapValues(nutrients, (v) => v+1))
// output :
// { carbohydrates: 13, protein: 21, fat: 6 }
console.log(reduceValues(nutrients, (acc, cr) => acc + cr))
// output :
// 37
```
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You will have a small database to help you with the groceries.
### Notions
- [devdocs.io/javascript/global_objects/array/filter](https://devdocs.io/javascript/global_objects/array/filter)
- [devdocs.io/javascript/global_objects/array/map](https://devdocs.io/javascript/global_objects/array/map)
- [devdocs.io/javascript/global_objects/array/reduce](https://devdocs.io/javascript/global_objects/array/reduce)
- [devdocs.io/javascript/global_objects/object/entries](https://devdocs.io/javascript/global_objects/object/entries)
- [devdocs.io/javascript/global_objects/object/fromentries](https://devdocs.io/javascript/global_objects/object/fromentries)
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### Code provided
> all code provided will be added to your solution and doesn't need to be submitted.
5 years ago
```js
// small database with nutrition facts, per 100 grams
// In this exercise this is used for testing purposes only
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// prettier-ignore
const nutritionDB = {
tomato: { calories: 18, protein: 0.9, carbs: 3.9, sugar: 2.6, fiber: 1.2, fat: 0.2 },
vinegar: { calories: 20, protein: 0.04, carbs: 0.6, sugar: 0.4, fiber: 0, fat: 0 },
oil: { calories: 48, protein: 0, carbs: 0, sugar: 123, fiber: 0, fat: 151 },
onion: { calories: 0, protein: 1, carbs: 9, sugar: 0, fiber: 0, fat: 0 },
garlic: { calories: 149, protein: 6.4, carbs: 33, sugar: 1, fiber: 2.1, fat: 0.5 },
paprika: { calories: 282, protein: 14.14, carbs: 53.99, sugar: 1, fiber: 0, fat: 12.89 },
sugar: { calories: 387, protein: 0, carbs: 100, sugar: 100, fiber: 0, fat: 0 },
orange: { calories: 49, protein: 0.9, carbs: 13, sugar: 9, fiber: 0.2, fat: 0.1 },
}
```