Returns the gradient of the curve at the point which is 'distance' from the given location. if this point is greater than location 1, the gradient at location 1 is returned. if this point is less than location 0, the gradient at location 0 is returned.
export declare function gradientAtPointAlongPathFrom(curve: Curve, location: number, distance: number): number;
a decimal between 0 and 1 inclusive.