IC Python API:RLPy RQuaternion
Contents
- 1 Detailed Description
- 2 Constructor & Destructor
- 3 Operator
- 4 Member Functions
- 4.1 AlmostEqual( self, qQ )
- 4.2 Conjugate( self )
- 4.3 Dot( self, qQ )
- 4.4 FromAxisAngle( self, rkAxis, fAngle )
- 4.5 FromRotationMatrix( self, rkRot )
- 4.6 Inverse( self, rkRot )
- 4.7 Multiply( self, qQ )
- 4.8 MultiplyEqual( self, qQ )
- 4.9 Normalize( self )
- 4.10 Rotate180( self )
- 4.11 SetX( self, tX )
- 4.12 SetY( self, tY )
- 4.13 SetZ( self, tZ )
- 4.14 SetW( self, tW )
- Main article: Modules.
- Last modified: 02/24/2020
Detailed Description
This class represents a quaternion in mathematics. Quaternions represetn directions as a single rotation, just as rectangular coordinates represent positions as single vector. RQuaternion also defines some constants that can be used directly:
Constant | Description |
---|---|
RQuaternion.IDENTITY | 4D zero vector: (0, 0, 0, 1) |
RQuaternion.ZERO | 4D x unit vector: (0, 0, 0, 0) |
Constructor & Destructor
__init__( self )
The constructor. Initialize a new RQuaternion object without initialization.
q = RLPy.RQuaternion()
print(str(q.x) + ', ' + str(q.y) + ', ' + str(q.z) + ', ' + str(q.w)) # random values
__init__( self, vV )
The constructor. Initialize a new RQuaternion object from a 4D vector RVector4.
v = RLPy.RVector4(1, 2, 3, 4)
q = RLPy.RQuaternion(v)
print(str(q.x) + ', ' + str(q.y) + ', ' + str(q.z) + ', ' + str(q.w)) # 1.0, 2.0, 3.0, 4.0
Parameters
- vV [IN] a 4D vector - RLPy.RVector4
__init__( self, qQ )
v = RLPy.RVector4(1, 2, 3, 4)
q = RLPy.RQuaternion(v)
p = RLPy.RQuaternion(q)
print(str(p.x) + ', ' + str(p.y) + ', ' + str(p.z) + ', ' + str(p.w)) # 1.0, 2.0, 3.0, 4.0
Parameters
- qQ [IN] a quaternion - RLPy.RQuaternion
__init__( self, kAxis, fAngle )
The constructor. Initialize a new RQuaternion object with Axis-angle. The axis is specified by a 3D vector, and the angle is specified by a float value.
v = RLPy.RVector3(0, 0, 1)
q = RLPy.RQuaternion(v, math.pi/2)
print(str(q.x) + ', ' + str(q.y) + ', ' + str(q.z) + ', ' + str(q.w))
# 0.0, 0.0, 0.7071067094802856, 0.7071067690849304
Parameters
- kAxis [IN] the rotation axis - RLPy.RVector3
- fAngle [IN] the rotation angle - float
__init__( self, kRot )
The constructor. Initialize a new RQuaternion object with a 3x3 rotation matrix.
Parameters
- kRot [IN] a 3x3 rotation matrix - RLPy.RMatrix3
v = RLPy.RVector3(0, 0, 1)
m = RLPy.RMatrix3(v, math.pi/2)
q = RLPy.RQuaternion(m)
print(str(q.x) + ', ' + str(q.y) + ', ' + str(q.z) + ', ' + str(q.w))
# 0.0, 0.0, 0.7071067690849304, 0.7071067690849304
Operator
=
The "equal to" operator.
q = RLPy.RQuaternion()
p = q
if q == p: # True
print("equal")
!=
The "not equal to" operator.
a = RLPy.RVector4(1, 2, 3, 4)
q = RLPy.RQuaternion(a)
b = RLPy.RVector4(2, 2, 3, 4)
p = RLPy.RQuaternion(b)
if a != b: #True
print("not equal")
<
The "less than" operator. Similar to string comparison: Returns True upon the first match that is less than and False if it is greater than. If the current comparison is equal, continue onto the next element. If all elements are equal then return False.
a = RLPy.RVector4(0, 1, 5, 2)
b = RLPy.RVector4(0, 1, 5, 3)
c = RLPy.RVector4(1, 0, 1, 0)
d = RLPy.RVector4(0, 1, 5, 2)
p = RLPy.RQuaternion(a)
q = RLPy.RQuaternion(b)
r = RLPy.RQuaternion(c)
s = RLPy.RQuaternion(d)
if p< q: #True
print('p< q')
if q< r: #True
print('q< r')
if p< s: #False
print('p< s')
>
The "greater than" operator. Similar to string comparison: Returns True upon the first match that is greater than and False if it is less than. If the current comparison is equal, continue onto the next element. If all elements are equal then return False.
a = RLPy.RVector4(0, 1, 5, 2)
b = RLPy.RVector4(0, 1, 5, 3)
c = RLPy.RVector4(1, 0, 1, 0)
d = RLPy.RVector4(0, 1, 5, 2)
p = RLPy.RQuaternion(a)
q = RLPy.RQuaternion(b)
r = RLPy.RQuaternion(c)
s = RLPy.RQuaternion(d)
if q >p: #True
print('q >p')
if r >q: #True
print('r >q')
if p >s: #False
print('p >s')
<=
The "less than or equal" operator. Similar to string comparison: Returns True upon the first match that is less than and False if it is greater than. If the current comparison is equal, continue onto the next element. If all elements are equal then return True.
a = RLPy.RVector4(0, 1, 5, 2)
b = RLPy.RVector4(0, 1, 5, 3)
c = RLPy.RVector4(1, 0, 1, 0)
d = RLPy.RVector4(0, 1, 5, 2)
p = RLPy.RQuaternion(a)
q = RLPy.RQuaternion(b)
r = RLPy.RQuaternion(c)
s = RLPy.RQuaternion(d)
if p<= q: #True
print('p<= q')
if q<= r: #True
print('q<= r')
if p<= s: #True
print('p<= s')
>=
The "greater than or equal" operator. Similar to string comparison: Returns True upon the first match that is greater than and False if it is less than. If the current comparison is equal, continue onto the next element. If all elements are equal then return True.
a = RLPy.RVector4(0, 1, 5, 2)
b = RLPy.RVector4(0, 1, 5, 3)
c = RLPy.RVector4(1, 0, 1, 0)
d = RLPy.RVector4(0, 1, 5, 2)
p = RLPy.RQuaternion(a)
q = RLPy.RQuaternion(b)
r = RLPy.RQuaternion(c)
s = RLPy.RQuaternion(d)
if q >= p: #True
print('q >= p')
if r >= q: #True
print('r >= q')
if p >= s: #True
print('p >= s')
+
The "addition" operator. Perform quaternion addition.
a = RLPy.RVector4(0, 1, 2, 3)
b = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
q = RLPy.RQuaternion(b)
r = p + q
print(str(r.x) + ', ' + str(r.y) + ', ' + str(r.z) + ', ' + str(r.w)) # 1.0, 3.0, 5.0, 7.0
-
The "subtraction" operator. Perform quaternion subtraction.
a = RLPy.RVector4(0, 1, 2, 3)
b = RLPy.RVector4(3, 2, 1, 0)
p = RLPy.RQuaternion(a)
q = RLPy.RQuaternion(b)
r = q - p
print(str(r.x) + ', ' + str(r.y) + ', ' + str(r.z) + ', ' + str(r.w)) # 3.0, 1.0, -1.0, -3.0
*
The "multiplication" operator. Perform a scalar multiplication when the second operand is an integer or float. If the second operand is another quaternion, then the respective elements are multiplied.
a = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
q = p * 2
r = p * p
print(str(q.x) + ', ' + str(q.y) + ', ' + str(q.z) + ', ' + str(q.w)) # 2.0, 4.0, 6.0, 8.0
print(str(r.x) + ', ' + str(r.y) + ', ' + str(r.z) + ', ' + str(r.w)) # 1.0, 4.0, 9.0, 16.0
/
The "division" operator. Perform a scalar division with a int or float value which the second operand is limited to.
a = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
q = p / 2
print(str(q.x) + ', ' + str(q.y) + ', ' + str(q.z) + ', ' + str(q.w)) # 0.5, 1.0, 1.5, 2.0
-
The "unary minus" operator. Inverse the sign of each element.
a = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
q = -p
print(str(q.x) + ', ' + str(q.y) + ', ' + str(q.z) + ', ' + str(q.w)) # -1.0, -2.0, -3.0, -4.0
+ =
The "addition assignment" operator.
a = RLPy.RVector4(0, 1, 2, 3)
b = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
q = RLPy.RQuaternion(b)
p += q
print(str(p.x) + ', ' + str(p.y) + ', ' + str(p.z) + ', ' + str(p.w)) # 1.0, 3.0, 5.0, 7.0
- =
The "subtraction assignment" operator.
a = RLPy.RVector4(0, 1, 4, 5)
b = RLPy.RVector4(1, 2, 3, 1)
p = RLPy.RQuaternion(a)
q = RLPy.RQuaternion(b)
p -= q
print(str(p.x) + ', ' + str(p.y) + ', ' + str(p.z) + ', ' + str(p.w)) # -1.0, -1.0, 1.0, 4.0
*=
The "multiplication assignment" operator. For calculation method, refer to the * operator.
a = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
p *= 2
print(str(p.x) + ', ' + str(p.y) + ', ' + str(p.z) + ', ' + str(p.w)) # 2.0, 4.0, 6.0, 8.0
/=
The "division assignment" operator. For calculation method, refer to the / operator.
a = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
p /= 2
print(str(p.x) + ', ' + str(p.y) + ', ' + str(p.z) + ', ' + str(p.w)) # 0.5, 1.0, 1.5, 2.0
Member Functions
AlmostEqual( self, qQ )
a = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
q = RLPy.RQuaternion(a)
r = RLPy.RQuaternion(a)
q.w = 4.000000001
r.w = 4.00001
if p.AlmostEqual(q): #True
print("p ≈ q")
if q.AlmostEqual(r): #False
print("p ≈ r")
Parameters
- qQ [IN] The target quaternion to check for equivalence - RLPy.RQuaternion
Returns
- True if the two quaternions are almost the same - bool
Conjugate( self )
Conjugate this quaternion.
a = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
q = p.Conjugate()
print(str(q.x) + ', ' + str(q.y) + ', ' + str(q.z) + ', ' + str(q.w)) # -1.0, -2.0, -3.0, 4.0
Returns
- Returns the conjugated quaternion. The result is a quaternion whose x, y, and z values have been negated - RLPy.RQuaternion
Dot( self, qQ )
Calculate dot product of the two quaternions.
Parameters
- qQ [IN] The quaternion to compute dot product - RLPy.RQuaternion
Returns
- Returns the value of the dot product - float
a = RLPy.RVector4(1, 2, 3, 4)
b = RLPy.RVector4(1, 2, 3, 0)
p = RLPy.RQuaternion(a)
q = RLPy.RQuaternion(b)
f = p.Dot(q)
print(f) # 14.0
FromAxisAngle( self, rkAxis, fAngle )
Quaternion from axis angle.
Parameters
- rkAxis [IN] axis vector - RLPy.RVector3
- fAngle [IN] angle in radians - float
Returns
- Return a new quaternion from a axis angle - RLPy.RQuaternion
p = RLPy.RQuaternion()
v = RLPy.RVector3(0, 0, 1)
p.FromAxisAngle(v, math.pi/2)
print(str(p.x) + ', ' + str(p.y) + ', ' + str(p.z) + ', ' + str(p.w)) # 0.0, 0.0, 0.7071067094802856, 0.7071067690849304
FromRotationMatrix( self, rkRot )
Quaternion from a rotation matrix.
Parameters
- rkRot [IN] Rotation matrix - RLPy.RMatrix3
Returns
- Return a new quaternion from a rotation matrix - RLPy.RQuaternion
v = RLPy.RVector3(0, 0, 1)
m = RLPy.RMatrix3(v, math.pi/2)
p = RLPy.RQuaternion()
p.FromRotationMatrix(m)
print(str(p.x) + ', ' + str(p.y) + ', ' + str(p.z) + ', ' + str(p.w)) # 0.0, 0.0, 0.7071067690849304, 0.7071067690849304
Inverse( self, rkRot )
Obtain the inverse of this quaternion.
Returns
- The inversed quaternion - RLPy.RQuaternion
a = RLPy.RVector4(1, 1, 1, 1)
p = RLPy.RQuaternion(a)
q = p.Inverse()
print(str(q.x) + ', ' + str(q.y) + ', ' + str(q.z) + ', ' + str(q.w)) # -0.25, -0.25, -0.25, 0.25
Multiply( self, qQ )
Multiply by another quaternion.
Parameters
- qQ [IN] The quaternion to multiply - RLPy.RQuaternion
Returns
- Returns the multiplied quaternion - RLPy.RQuaternion
a = RLPy.RVector4(1, 2, 3, 4)
b = RLPy.RVector4(1, 2, 2, 1)
p = RLPy.RQuaternion(a)
q = RLPy.RQuaternion(b)
r = p.Multiply(q)
print(str(r.x) + ', ' + str(r.y) + ', ' + str(r.z) + ', ' + str(r.w)) # 3.0, 11.0, 11.0, -7.0
MultiplyEqual( self, qQ )
Parameters
- qQ [IN] The quaternion to multiply - RLPy.RQuaternion
Returns
- Returns the multiplied quaternion - RLPy.RQuaternion
a = RLPy.RVector4(1, 2, 3, 4)
b = RLPy.RVector4(1, 2, 2, 1)
p = RLPy.RQuaternion(a)
q = RLPy.RQuaternion(b)
r = p.MultiplyEqual(q)
print(str(r.x) + ', ' + str(r.y) + ', ' + str(r.z) + ', ' + str(r.w)) # 3.0, 11.0, 11.0, -7.0
Normalize( self )
Normalizes this quaternion.
Returns
- Returns the normalized quaternion - RLPy.RQuaternion
a = RLPy.RVector4(1, 1, 1, 1)
p = RLPy.RQuaternion(a)
q = p.Normalize()
print(str(q.x) + ', ' + str(q.y) + ', ' + str(q.z) + ', ' + str(q.w))
# 0.4999999701976776, 0.4999999701976776, 0.4999999701976776, 0.4999999701976776
Rotate180( self )
Rotate 180 degree of this quaternion.
Returns
- Returns the rotated quaternion - RLPy.RQuaternion
a = RLPy.RVector4(1, 1, 1, 1)
p = RLPy.RQuaternion(a)
q = p.Normalize()
print(str(q.x) + ', ' + str(q.y) + ', ' + str(q.z) + ', ' + str(q.w))
#0.4999999701976776, 0.4999999701976776, 0.4999999701976776, 0.4999999701976776
SetX( self, tX )
Set the value of the x-axis.
Parameters
- tX [IN] the value of the x-axis - float
a = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
p.SetX(9)
print(str(p.x) + ', ' + str(p.y) + ', ' + str(p.z) + ', ' + str(p.w)) # 9.0, 2.0, 3.0, 4.0
SetY( self, tY )
Set the value of the y-axis.
Parameters
- tY [IN] the value of the y-axis - float
a = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
p.SetY(9)
print(str(p.x) + ', ' + str(p.y) + ', ' + str(p.z) + ', ' + str(p.w))
#1.0, 9.0, 3.0, 4.0
SetZ( self, tZ )
Set the value of the z-axis.
Parameters
- tZ [IN] the value of the z-axis - float
a = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
p.SetZ(9)
print(str(p.x) + ', ' + str(p.y) + ', ' + str(p.z) + ', ' + str(p.w))
#1.0, 2.0, 9.0, 4.0
SetW( self, tW )
Set the value of the w-axis.
Parameters
- tW [IN] the value of the w-axis - float
a = RLPy.RVector4(1, 2, 3, 4)
p = RLPy.RQuaternion(a)
p.SetW(9)
print(str(p.x) + ', ' + str(p.y) + ', ' + str(p.z) + ', ' + str(p.w))
#1.0, 2.0, 3.0, 9.0