Vectors are used everywhere in FreeCAD.
Example:
v=FreeCAD.Vector()
v=FreeCAD.Vector(1,0,0)
v=FreeCAD.Base.Vector()
v2 = FreeCAD.Vector(3,2,-5)
v3 = v.add(v2)
print v3.Length
LengthReturns: returns the length of the vector.
add(Vector)Description: adds another vector to this one.
Returns: vector
cross(Vector)Description: the crossproduct between this vector and another.
Returns: vector
distanceToLine(Vector1,Vector2)Description: the distance between the vector and a line through Vector1 in direction Vector2.
Returns: float
distanceToPoint(Vector)Description: the distance between this vector and another.
Returns: float
distanceToLineSegment(Vector1,Vector2)Description: a vector to the closest point on a line segment from Vector1 to Vector2.
Returns: Vector
distanceToPlane(Vector1,Vector2)Description: the distance between the vector and a plane defined by a point and a normal.
Returns: float
dot(Vector)Description: the dot product between 2 vectors.
Returns: float
getAngle(Vector)Description: the angle in radians between this vector and another.
Returns: float
isEqual(Vector2,tolerance)Description: Checks if the distance between the points represented by this Vector and Vector2 is less than or equal to the given tolerance.
Returns: True/False
isNormal(Vector2,tolerance)Description: Checks if this Vector is normal to Vector2 within the tolerance.
Returns: True/False
isOnLineSegment(Vector1,Vector2)Description: Checks if this vector is on the line segment generated by Vector1 and Vector2.
Returns: Vector
isParallel(Vector2,tolerance)Description: Checks if this Vector is parallel to Vector2 within the tolerance.
Returns: True/False
multiply(Float)Description: multiplies (uniform scale) a vector by the given factor.
Returns: nothing
negative(Vector)Description: Returns the negative (opposite) of this vector.
Returns: Vector
normalize( )Description: normalizes a vector (sets its length to 1.0).
Returns: nothing
projectToLine(Vector1,Vector2)Description: projects the vector on a line through Vector1 in direction Vector2.
Returns: nothing
projectToPlane(Vector1,Vector2)Description: projects the vector on a plane defined by a point (Vector1) and a normal (Vector2).
Returns: nothing
scale(Float,Float,Float)Description: Same as multiply but lets specify different values for x, y and z directions. (non-uniform scale)
Returns: nothing
sub(Vector)Description: subtracts another vector from this one.
Returns: vector
xReturns: the x coordinate of a vector.
yReturns: the y coordinate of a vector.
zReturns: the z coordinate of a vector.
This page is retrieved from https://wiki.freecad.org/Vector_API