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DAStatic Functions Relevant to DAVector2 Objects
DAStatics Class
AddVector2Creates a DAVector2 object that is the vector-valued sum of the two vectors.
lib.AddVector2(
v1,
v2
)Parameters
- v1 and v2
- The DAVector2 objects to be added.
Return Values
Returns the DAVector2 object.
See Also
DAStatics Class
DerivativeVector2Creates a DAVector2 object that is the instantaneous derivative (rate of change) of the given vector. For example, a constant vector yields a constant derivative of [0 0], and Vector2 (time, 0) (without any additional time substitutions) yields a constant derivative vector of [1 0].
lib.DerivativeVector2(
vec
)Parameters
- vec
- A DAVector2 object.
Return Values
Returns the DAVector2 object.
DAStatics Class
DotVector2Creates a DANumber object that represent the "dot product" of the given vectors. The dot product is the product of the lengths of the vectors and the cosine of the angle between them.
lib.DotVector2(
v1,
v2
)Parameters
- v1 and v2
- The DAVector2 objects.
Return Values
Returns the DANumber object.
DAStatics Class
IntegralVector2Creates a DAVector2 object that represents the sum of the all values of vec from the given start time to the present.
lib.IntegralVector2(
vec
)Parameters
- a
- The DAVector2 object.
Return Values
Returns the DAVector2 object.
DAStatics Class
NegVector2Creates a DAVector2 object that is the same length as the original vector but points in the opposite direction.
lib.NegVector2(
v1
)Parameters
- v1
- A DAVector2 object that is the original vector.
Return Values
Returns the DAVector2 object.
DAStatics Class
SubVector2Creates a DAVector2 object. The direction and length of the vector are calculated by subtracting the coordinates of v2 from the corresponding coordinates of v1.
lib.SubVector2(
v1,
v2
)Parameters
- v1 and v2
- The DAVector2 objects.
Return Values
Returns the DAVector2 object.
See Also
DAStatics Class
Vector2AnimCreates a DAVector2 object having a direction and length as specified by the given Cartesian coordinates.
lib.Vector2Anim(
x,
y
)Parameters
- x
- The DANumber object specifying the distance along the x-axis from the origin to a point. This must be an animated number.
- y
- The DANumber object specifying the distance along the y-axis. This must be an animated number.
Return Values
Returns the DAVector2 object.
See Also
DAStatics Class
Vector2Same as Vector2Anim except that x and y are non-animated numbers (doubles).
lib.Vector2(
x,
y
)DAStatics Class
Vector2BSplineCreates a DAVector2 object based on a B-spline function. The function depends on the control elements, the knot vector, the mathematical degree, and the weights of the control elements (these are optional).
A B-spline function without weights is piecewise polynomial and with weights is piecewise rational (the quotient of two polynomials). It requires that:
numberOfControlElements = numberOfKnots - degree + 1
The control elements define the approximate direction and shape of the function. The knots represent junction values, in parameter space, between the connected polynomial parts.
Given a degree d and a number of knots k, the function is valid in the range knotd to knotk-d+1, and is otherwise undefined. For example, for a degree 2 curve, the valid range is from the second knot to the next to the last knot, inclusive.
The returned DAVector2 is the traversal of the spline function according to the evaluation parameter. The evaluation parameter is a DANumber that must be in the valid range of the spline, which is [knotd, knotk-d+1]. Any values outside this range are automatically clamped to the end values.
lib.Vector2BSpline(
degree,
knots,
control_elements,
weights,
evaluation
)Parameters
- degree
- A number (a long) representing the mathematical degree of the B-spline to evaluate. Must be 1, 2, or 3.
- knots
- An array (variant) of DANumber objects representing the knots used to calculate the B-spline.
- control_elements
- An array (variant) of DAPoint2 objects representing the control elements used to calculate the B-spline.
- weights
- An array (variant) of DANumber objects representing the weights used to calculate the rational B-spline. There must be the same number of weights as control elements. For non-rational B-splines, the value of weights is null.
- evaluation
- A DANumber object that controls the spline evaluation. This must be an animated number.
Return Values
Returns the DAVector2 object.
DAStatics Class
Vector2PolarAnimCreates a DAVector2 object having a direction and length as specified by the given polar coordinates.
lib.Vector2PolarAnim(
XYangle,
length
)Parameters
- XYangle
- The DANumber object that is the counter-clockwise angle of the vector, in radians, from the positive x-ray. This must be an animated number.
- length
- The DANumber object that is the length of the vector. This must be an animated number.
Return Values
Returns the DAVector2 object.
See Also
DAStatics Class
Vector2PolarSame as Vector2PolarAnim except that XYangle and length are non-animated numbers (doubles).
lib.Vector2Polar(
XYangle,
length
)DAStatics Class
Vector2PolarDegreesCreates a DAVector2 object having a direction and length as specified by the given polar coordinates.
lib.Vector2PolarDegrees(
XYangle,
length
)Parameters
- XYangle
- The number (a double) that is the counter-clockwise angle of the vector (expressed in degrees) from the positive x-ray.
- length
- The number (a double) that is the length of the vector.
Return Values
Returns the DAVector2 object.
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