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Do you still remember the formula for the volume of a cylinder? Today we will introduce to you how to calculate the volume of a cylinder through JavaScript and keep 4 decimal places~
First of all, let’s recall the formula for the volume of a cylinder:
Volume of a cylinder = base area , or
v=1/2ch×r (half of the side area × radius)
Go directly to the code:
<!DOCTYPE HTML>
<html>
<head>
<meta charset="UTF-8">
<script>
function Cylinder(cyl_height, cyl_diameter) {
this.cyl_height = cyl_height;
this.cyl_diameter = cyl_diameter;
}
Cylinder.prototype.Volume = function () {
var radius = this.cyl_diameter / 2;
return this.cyl_height * Math.PI * radius * radius;
};
var cyl = new Cylinder(7, 4);
console.log('体积 =', cyl.Volume().toFixed(4));
</script>
</head>
<body>
</body>
</html>The calculation result is:
Note:
PI attribute is π, that is The ratio of the circumference of a circle to its diameter. This value is approximately 3.141592653589793. Its syntax is "Math.PI". 
→With an introduction to π:
Pi (π) is the ratio of the circumference to the diameter of a circle. It is generally represented by the Greek letter π and is used in mathematics and physics. A universal mathematical constant. π is also equal to the ratio of the area of a circle to the square of its radius. It is also a key value for accurately calculating geometric shapes such as circle circumference, circle area, and sphere volume. And in analysis, π can be defined very strictly as the smallest positive real number x that satisfies sinx = 0.
Finally, I would like to recommend "JavaScript Basics Tutorial
" ~ Welcome everyone to learn ~The above is the detailed content of Calculate the volume of a cylinder with javascript and keep 4 decimal places. For more information, please follow other related articles on the PHP Chinese website!