Because you are initializing an array you could use the Array.from
syntax.
This would allow you to declare and initialize your array on the same line.
const value = 300000;
const yaxispoints = value / 10;
const array1= Array.from({length: 11}, (v,i) => i * yaxispoints);
array1.forEach(v => console.log(v));
solved Assign values to array javascript