var instance; // Type: wijmo.chart.chart_animation;
var value; // Type: string
value = instance.easing;

var easing : string;

Return Value

Valid Values:

• easeInCubic – Cubic easing in. Begins at zero velocity and then accelerates.
• easeOutCubic – Cubic easing in and out. Begins at full velocity and then decelerates to zero.
• easeInOutCubic – Begins at zero velocity, accelerates until halfway, and then decelerates to zero velocity again.
• easeInBack – Begins slowly and then accelerates.
• easeOutBack – Begins quickly and then decelerates.
• easeOutElastic – Begins at full velocity and then decelerates to zero.
• easeOutBounce – Begins quickly and then decelerates. The number of bounces is related to the duration; a longer duration produces more bounces.

You can create custom easing animations using jQuery UI Easings.

Easing is defined in Raphael. You can find external documentation here:  http://raphaeljs.com/reference.html#Raphael.easing_formulas

Reference

chart_animation Interface