Source code for sas.qtgui.Plotting.Slicers.Arc

"""
    Arc slicer for 2D data
"""
import numpy as np

from sas.qtgui.Plotting.Slicers.BaseInteractor import BaseInteractor

[docs]class ArcInteractor(BaseInteractor): """ Select an annulus through a 2D plot """
[docs] def __init__(self, base, axes, color='black', zorder=5, r=1.0, theta1=np.pi / 8, theta2=np.pi / 4): BaseInteractor.__init__(self, base, axes, color=color) self.markers = [] self.axes = axes self._mouse_x = r self._mouse_y = 0 self._save_x = r self._save_y = 0 self.scale = 10.0 self.theta1 = theta1 self.theta2 = theta2 self.radius = r [self.arc] = self.axes.plot([], [], linestyle='-', marker='', color=self.color) self.npts = 20 self.has_move = False self.connect_markers([self.arc]) self.update()
[docs] def set_layer(self, n): """ Allow adding plot to the same panel :param n: the number of layer """ self.layernum = n self.update()
[docs] def clear(self): """ Clear this slicer and its markers """ self.clear_markers() try: for item in self.markers: item.remove() self.arc.remove() except: # Old version of matplotlib for item in range(len(self.axes.lines)): del self.axes.lines[0]
[docs] def get_radius(self): """ Return arc radius """ radius = np.sqrt(np.power(self._mouse_x, 2) + \ np.power(self._mouse_y, 2)) return radius
[docs] def update(self, theta1=None, theta2=None, nbins=None, r=None): """ Update the plotted arc :param theta1: starting angle of the arc :param theta2: ending angle of the arc :param nbins: number of points along the arc :param r: radius of the arc """ # Plot inner circle x = [] y = [] if theta1 is not None: self.theta1 = theta1 if theta2 is not None: self.theta2 = theta2 while self.theta2 < self.theta1: self.theta2 += (2 * np.pi) while self.theta2 >= (self.theta1 + 2 * np.pi): self.theta2 -= (2 * np.pi) self.npts = int((self.theta2 - self.theta1) / (np.pi / 120)) if r is None: self.radius = np.sqrt(np.power(self._mouse_x, 2) + \ np.power(self._mouse_y, 2)) else: self.radius = r for i in range(self.npts): phi = (self.theta2 - self.theta1) / (self.npts - 1) * i + self.theta1 xval = 1.0 * self.radius * np.cos(phi) yval = 1.0 * self.radius * np.sin(phi) x.append(xval) y.append(yval) self.arc.set_data(x, y)
[docs] def save(self, ev): """ Remember the roughness for this layer and the next so that we can restore on Esc. """ self._save_x = self._mouse_x self._save_y = self._mouse_y self.base.freeze_axes()
[docs] def moveend(self, ev): """ After a dragging motion reset the flag self.has_move to False :param ev: event """ self.has_move = False self.base.moveend(ev)
[docs] def restore(self): """ Restore the roughness for this layer. """ self._mouse_x = self._save_x self._mouse_y = self._save_y
[docs] def move(self, x, y, ev): """ Process move to a new position, making sure that the move is allowed. """ self._mouse_x = x self._mouse_y = y self.has_move = True self.base.base.update()
[docs] def set_cursor(self, radius, phi_min, phi_max, nbins): """ """ self.theta1 = phi_min self.theta2 = phi_max self.update(nbins=nbins, r=radius)
[docs] def get_params(self): """ """ params = {} params["radius"] = self.radius params["theta1"] = self.theta1 params["theta2"] = self.theta2 return params
[docs] def set_params(self, params): """ """ x = params["radius"] phi_max = self.theta2 nbins = self.npts self.set_cursor(x, self._mouse_y, phi_max, nbins)