109 lines
2.6 KiB
Python
109 lines
2.6 KiB
Python
import math
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class Vector:
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""" 3D Vector
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Simple class that represents a 3D vector
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"""
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def __init__(self, x = 0.0, y = 0.0, z = 0.0):
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"""
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Creates a vector from it's coordinates
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"""
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self.x = x
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self.y = y
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self.z = z
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def from_array(self, arr):
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"""
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Creates a vector from an array
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"""
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self.x = float(arr[0]) if len(arr) > 0 else None
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self.y = float(arr[1]) if len(arr) > 1 else None
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self.z = float(arr[2]) if len(arr) > 2 else None
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return self
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def __add__(self, other):
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"""
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Sums two vectors
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"""
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return Vector(self.x + other.x, self.y + other.y, self.z + other.z)
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def __sub__(self, other):
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"""
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Subs two vectors
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"""
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return Vector(self.x - other.x, self.y - other.y, self.z - other.z)
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def __mul__(self, other):
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"""
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Computes the product between a vector and a number
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"""
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return Vector(self.x * other, self.y * other, self.z * other)
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def __truediv__(self, number):
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self.x /= number
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self.y /= number
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self.z /= number
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return self
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def __rmul__(self, other):
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"""
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Computes the product between a vector and a number
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"""
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return self.__mul__(other)
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def norm2(self):
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"""
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Computes the square of the norm of a vector
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"""
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return self.x * self.x + self.y * self.y + self.z * self.z
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def norm(self):
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"""
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Compute the norm of a vector
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"""
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return math.sqrt(self.norm2())
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def normalize(self):
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"""
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Divides each coordinate of the vector by its norm
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"""
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norm = self.norm()
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if abs(norm) > 0.0001:
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self.x /= norm
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self.y /= norm
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self.z /= norm
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def cross_product(v1, v2):
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"""
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Computes the cross product between the two vectors
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"""
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return Vector(
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v1.y * v2.z - v1.z * v2.y,
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v1.z * v2.x - v1.x * v2.z,
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v1.x * v2.y - v1.y * v2.x)
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def from_points(v1, v2):
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"""
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Creates a vector from two points
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"""
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return Vector(
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v2.x - v1.x,
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v2.y - v1.y,
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v2.z - v1.z)
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def __str__(self):
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"""
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Prints the coordinates of the vector between partheses
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"""
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return '(' + ", ".join([str(self.x), str(self.y), str(self.z)]) + ")"
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def dot(self, other):
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"""
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Computes the dot product of two vectors
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"""
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return self.x * other.x + self.y * other.y + self.z * other.z
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