function rotateAboutY (vec, length, theta)
    local initialTheta = math.atan(vec.z/vec.x)
    local initialPhi = math.atan((math.sqrt((vec.x)^2 + (vec.z)^2))/vec.y)
    r = vec:magnitude()
    --Calculate new values
    local newLength = r + length
    local newTheta = initialTheta + theta
    local newPhi = initialPhi
    --Convert to Cartesian
    local newX = newLength * math.sin(newPhi) * math.cos(newTheta)
    local newY = newLength * math.cos(newPhi)
    local newZ = newLength * math.sin(newPhi) * math.sin(newTheta)
    --set vector
    local resultant = vector():set(newX, newY, newZ)

    return resultant
end

function rotateAboutX (vec, length, theta)
    local initialTheta = math.atan(vec.z/vec.y)
    local initialPhi = math.atan((math.sqrt((vec.y)^2 + (vec.z)^2))/vec.x)
    r = vec:magnitude()
    --Calculate new values
    local newLength = r + length
    local newTheta = initialTheta + theta
    local newPhi = initialPhi
    --Convert to Cartesian
    local newX = newLength * math.cos(newPhi)
    local newY = newLength * math.sin(newPhi) * math.sin(newTheta)
    local newZ = newLength * math.sin(newPhi) * math.cos(newTheta)
    --set vector
    local resultant = vector():set(newX, newY, newZ)

    return resultant
end

function rotateAboutZ (vec, length, theta)
    local initialTheta = math.atan(vec.y/vec.x)
    local initialPhi = math.atan((math.sqrt((vec.x)^2 + (vec.y)^2))/vec.z)
    r = vec:magnitude()
    --Calculate new values
    local newLength = r + length
    local newTheta = initialTheta + theta
    local newPhi = initialPhi
    --Convert to Cartesian
    local newX = newLength * math.sin(newPhi) * math.cos(newTheta)
    local newY = newLength * math.sin(newPhi) * math.sin(newTheta)
    local newZ = newLength * math.cos(newPhi)
    --set vector
    local resultant = vector():set(newX, newY, newZ)

    return resultant
end