from __future__ import absolute_import from constants import * from mobject.svg.tex_mobject import TexMobject from mobject.types.vectorized_mobject import VGroup from mobject.types.vectorized_mobject import VMobject from mobject.geometry import Arrow from mobject.geometry import Line from utils.bezier import interpolate from utils.config_ops import digest_config class NumberLine(VMobject): CONFIG = { "color" : BLUE, "x_min" : -FRAME_X_RADIUS, "x_max" : FRAME_X_RADIUS, "unit_size" : 1, "tick_size" : 0.1, "tick_frequency" : 1, "leftmost_tick" : None, #Defaults to value near x_min s.t. 0 is a tick "numbers_with_elongated_ticks" : [0], "numbers_to_show" : None, "longer_tick_multiple" : 2, "number_at_center" : 0, "number_scale_val" : 0.75, "label_direction" : DOWN, "line_to_number_buff" : MED_SMALL_BUFF, "include_tip" : False, "propagate_style_to_family" : True, } def __init__(self, **kwargs): digest_config(self, kwargs) if self.leftmost_tick is None: tf = self.tick_frequency self.leftmost_tick = tf*np.ceil(self.x_min/tf) VMobject.__init__(self, **kwargs) if self.include_tip: self.add_tip() def generate_points(self): self.main_line = Line(self.x_min*RIGHT, self.x_max*RIGHT) self.tick_marks = VGroup() self.add(self.main_line, self.tick_marks) rounding_value = int(-np.log10(0.1*self.tick_frequency)) rounded_numbers_with_elongated_ticks = np.round( self.numbers_with_elongated_ticks, rounding_value ) for x in self.get_tick_numbers(): rounded_x = np.round(x, rounding_value) if rounded_x in rounded_numbers_with_elongated_ticks: tick_size_used = self.longer_tick_multiple*self.tick_size else: tick_size_used = self.tick_size self.add_tick(x, tick_size_used) self.stretch(self.unit_size, 0) self.shift(-self.number_to_point(self.number_at_center)) def add_tick(self, x, size = None): self.tick_marks.add(self.get_tick(x, size)) return self def get_tick(self, x, size = None): if size is None: size = self.tick_size result = Line(size*DOWN, size*UP) result.rotate(self.main_line.get_angle()) result.move_to(self.number_to_point(x)) return result def get_tick_marks(self): return self.tick_marks def get_tick_numbers(self): epsilon = 0.001 return np.arange( self.leftmost_tick, self.x_max+epsilon, self.tick_frequency ) def number_to_point(self, number): alpha = float(number-self.x_min)/(self.x_max - self.x_min) return interpolate( self.main_line.get_start(), self.main_line.get_end(), alpha ) def point_to_number(self, point): left_point, right_point = self.main_line.get_start_and_end() full_vect = right_point-left_point def distance_from_left(p): return np.dot(p-left_point, full_vect)/np.linalg.norm(full_vect) return interpolate( self.x_min, self.x_max, distance_from_left(point)/distance_from_left(right_point) ) def default_numbers_to_display(self): if self.numbers_to_show is not None: return self.numbers_to_show return np.arange(int(self.leftmost_tick), int(self.x_max)+1) def get_number_mobjects(self, *numbers, **kwargs): #TODO, handle decimals if len(numbers) == 0: numbers = self.default_numbers_to_display() if "force_integers" in kwargs and kwargs["force_integers"]: numbers = map(int, numbers) result = VGroup() for number in numbers: mob = TexMobject(str(number)) mob.scale(self.number_scale_val) mob.next_to( self.number_to_point(number), self.label_direction, self.line_to_number_buff, ) result.add(mob) return result def get_labels(self): return self.get_number_mobjects() def add_numbers(self, *numbers, **kwargs): self.numbers = self.get_number_mobjects( *numbers, **kwargs ) self.add(*self.numbers) return self def add_tip(self): start, end = self.main_line.get_start_and_end() vect = (end - start)/np.linalg.norm(end-start) arrow = Arrow(start, end + MED_SMALL_BUFF*vect, buff = 0) tip = arrow.tip tip.set_color(self.color) self.tip = tip self.add(tip) class UnitInterval(NumberLine): CONFIG = { "x_min" : 0, "x_max" : 1, "unit_size" : 6, "tick_frequency" : 0.1, "numbers_with_elongated_ticks" : [0, 1], "number_at_center" : 0.5, }