arrayFromProps.md

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arrayFromProps(obj, props, fallbackVal = null)

Pushes the values of all given properties (props) of an object (obj) into an array and returns that array. This is useful e.g. when data over time is given like the yearly gdp of a country, and you don't want to access every year by a specific property. If any of the given props does not exist, fallbackValue (default value is null) is pushed into the array.

Examples:

Example 1:

If you have data like this:

let rescuedPeople = {
  "Mon": 4,
  "Tue": 9,
  "Wed": 12,
  "Thu": 4,
  "Fri": 29,
  "Sat": 1
}

This takes all elements in days as properties of rescuedPeople and pushes the corresponding property values into an array. As we don't want null for Sunday ("Sun"), we set fallbackValue to 0:

let days = ["Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"];
let rescueCount = gmynd.arrayFromProps(rescuedPeople, days, 0);

This is the result:

[4, 9, 12, 4, 29, 1, 0]

Example 2:

Let's take this data here representing economic growth of Burundi from 1961 to 2016:

let growthValues = {
  "1961": -13.74613505,
  "1962": 9.063157935,
  // [...]
  "2015": -3.921142749,
  "2016": -0.570434452
};

In many cases like this you should consider writing a quick for-loop to get all needed properties into an array:

let properties = [];
for (let i = 1961; i < 2016; i++) {
  properties.push(i.toString());
}

Then, it works the same as before:

let growthArray = gmynd.arrayFromProps(growthValues, properties);

This is the result:

[-13.74613505, 9.063157935, /* [...] */, -3.921142749, -0.570434452]