def refine_pixels(interval_list): """ Evaluates the intervals and subdivides the interval if the expression is partially satisfied.""" temp_interval_list = [] plot_list = [] for intervals in interval_list: #Convert the array indices to x and y values intervalx = intervals[0] intervaly = intervals[1] func_eval = func(intervalx, intervaly) #The expression is valid in the interval. Change the contour #array values to 1. if func_eval[1] is False or func_eval[0] is False: pass elif func_eval == (True, True): plot_list.append([intervalx, intervaly]) elif func_eval[1] is None or func_eval[0] is None: #Subdivide avgx = intervalx.mid avgy = intervaly.mid a = interval(intervalx.start, avgx) b = interval(avgx, intervalx.end) c = interval(intervaly.start, avgy) d = interval(avgy, intervaly.end) temp_interval_list.append([a, c]) temp_interval_list.append([a, d]) temp_interval_list.append([b, c]) temp_interval_list.append([b, d]) return temp_interval_list, plot_list
def get_raster(self): func = experimental_lambdify((self.var_x, self.var_y), self.expr, use_interval=True) xinterval = interval(self.start_x, self.end_x) yinterval = interval(self.start_y, self.end_y) try: temp = func(xinterval, yinterval) except AttributeError: if self.use_interval_math: warnings.warn("Adaptive meshing could not be applied to the" " expression. Using uniform meshing.") self.use_interval_math = False if self.use_interval_math: return self._get_raster_interval(func) else: return self._get_meshes_grid()
def _get_raster_interval(self, func): """ Uses interval math to adaptively mesh and obtain the plot""" k = self.depth interval_list = [] #Create initial 32 divisions np = import_module('numpy') xsample = np.linspace(self.start_x, self.end_x, 33) ysample = np.linspace(self.start_y, self.end_y, 33) #Add a small jitter so that there are no false positives for equality. # Ex: y==x becomes True for x interval(1, 2) and y interval(1, 2) #which will draw a rectangle. jitterx = (np.random.rand( len(xsample)) * 2 - 1) * (self.end_x - self.start_x) / 2**20 jittery = (np.random.rand( len(ysample)) * 2 - 1) * (self.end_y - self.start_y) / 2**20 xsample += jitterx ysample += jittery xinter = [interval(x1, x2) for x1, x2 in zip(xsample[:-1], xsample[1:])] yinter = [interval(y1, y2) for y1, y2 in zip(ysample[:-1], ysample[1:])] interval_list = [[x, y] for x in xinter for y in yinter] plot_list = [] #recursive call refinepixels which subdivides the intervals which are #neither True nor False according to the expression. def refine_pixels(interval_list): """ Evaluates the intervals and subdivides the interval if the expression is partially satisfied.""" temp_interval_list = [] plot_list = [] for intervals in interval_list: #Convert the array indices to x and y values intervalx = intervals[0] intervaly = intervals[1] func_eval = func(intervalx, intervaly) #The expression is valid in the interval. Change the contour #array values to 1. if func_eval[1] is False or func_eval[0] is False: pass elif func_eval == (True, True): plot_list.append([intervalx, intervaly]) elif func_eval[1] is None or func_eval[0] is None: #Subdivide avgx = intervalx.mid avgy = intervaly.mid a = interval(intervalx.start, avgx) b = interval(avgx, intervalx.end) c = interval(intervaly.start, avgy) d = interval(avgy, intervaly.end) temp_interval_list.append([a, c]) temp_interval_list.append([a, d]) temp_interval_list.append([b, c]) temp_interval_list.append([b, d]) return temp_interval_list, plot_list while k >= 0 and len(interval_list): interval_list, plot_list_temp = refine_pixels(interval_list) plot_list.extend(plot_list_temp) k = k - 1 #Check whether the expression represents an equality #If it represents an equality, then none of the intervals #would have satisfied the expression due to floating point #differences. Add all the undecided values to the plot. if self.has_equality: for intervals in interval_list: intervalx = intervals[0] intervaly = intervals[1] func_eval = func(intervalx, intervaly) if func_eval[1] and func_eval[0] is not False: plot_list.append([intervalx, intervaly]) return plot_list, 'fill'
def _get_raster_interval(self, func): """ Uses interval math to adaptively mesh and obtain the plot""" k = self.depth interval_list = [] #Create initial 32 divisions xsample = np.linspace(self.start_x, self.end_x, 33) ysample = np.linspace(self.start_y, self.end_y, 33) #Add a small jitter so that there are no false positives for equality. # Ex: y==x becomes True for x interval(1, 2) and y interval(1, 2) #which will draw a rectangle. jitterx = (np.random.rand(len(xsample)) * 2 - 1) * (self.end_x - self.start_x) / 2**20 jittery = (np.random.rand(len(ysample)) * 2 - 1) * (self.end_y - self.start_y) / 2**20 xsample += jitterx ysample += jittery xinter = [interval(x1, x2) for x1, x2 in zip(xsample[:-1], xsample[1:])] yinter = [interval(y1, y2) for y1, y2 in zip(ysample[:-1], ysample[1:])] interval_list = [[x, y] for x in xinter for y in yinter] plot_list = [] #recursive call refinepixels which subdivides the intervals which are #neither True nor False according to the expression. def refine_pixels(interval_list): """ Evaluates the intervals and subdivides the interval if the expression is partially satisfied.""" temp_interval_list = [] plot_list = [] for intervals in interval_list: #Convert the array indices to x and y values intervalx = intervals[0] intervaly = intervals[1] func_eval = func(intervalx, intervaly) #The expression is valid in the interval. Change the contour #array values to 1. if func_eval[1] is False or func_eval[0] is False: pass elif func_eval == (True, True): plot_list.append([intervalx, intervaly]) elif func_eval[1] is None or func_eval[0] is None: #Subdivide avgx = intervalx.mid avgy = intervaly.mid a = interval(intervalx.start, avgx) b = interval(avgx, intervalx.end) c = interval(intervaly.start, avgy) d = interval(avgy, intervaly.end) temp_interval_list.append([a, c]) temp_interval_list.append([a, d]) temp_interval_list.append([b, c]) temp_interval_list.append([b, d]) return temp_interval_list, plot_list while k >= 0 and len(interval_list): interval_list, plot_list_temp = refine_pixels(interval_list) plot_list.extend(plot_list_temp) k = k - 1 #Check whether the expression represents an equality #If it represents an equality, then none of the intervals #would have satisfied the expression due to floating point #differences. Add all the undecided values to the plot. if self.has_equality: for intervals in interval_list: intervalx = intervals[0] intervaly = intervals[1] func_eval = func(intervalx, intervaly) if func_eval[1] and func_eval[0] is not False: plot_list.append([intervalx, intervaly]) return plot_list, 'fill'