The baseVal property of the SVGAnimatedNumber interface represents the base (non-animated) value of an animatable numeric attribute.
Some animatable SVG attributes accept a single numeric value, such as the radius attribute of the <circle> or <ellipse> elements and the width and height attributes of the <rect> element, and many others. The baseVal property reflects and updates the base, or non-animated, value of the numeric attribute.
A number; the base value of the attribute as a float.
This example includes a <path> element with a nested <animate> element that animates the value of the path's pathLength attribute:
<path d="M 0,40 h100" pathLength="90" id="path">
<animate
attributeName="pathLength"
values="50; 90; 50;"
dur="10s"
repeatCount="indefinite" />
</path>const path = document.querySelector("path");
console.log(path.pathLength.baseVal); // output: 90
path.pathLength.baseVal = 50; // updates the value
console.log(path.pathLength.baseVal); // output: 90The baseVal reflect that value of the pathLength attribute. We also use the baseVal property to access the base (non-animating) value of the animating pathLength.
To access the current value of the pathLength value as it animates, use the SVGAnimatedNumber.animVal property.