docstr: Update system using Euler's method (equivalent to order 1
  Runge-Kutta Method).
docstr_tok: ["Update","system","using","Euler","'s","method","(","equivalent","to","order","1","Runge-Kutta","Method",")","."]
code: def _euler_update(self, dt):
      """Update system using Euler's method (equivalent to order 1
      Runge-Kutta Method).
      """
      # Calculate the second derivative of x
      x_dd_t1 = -self.b * self.x_dot * np.abs(self.x_dot)
      x_dd_t2 = -self.spring_k1 * (self.x + self.d2 * self.theta)
      x_dot_dot = (x_dd_t1 + x_dd_t2) / self.little_m
  
      # Calculate the second derivative of theta
      term1 = -self.spring_k1 * self.d2 * self.x
      term2 = -self.theta * (
          self.spring_k1 * (self.d2**2)
          + self.spring_k2 * (self.d1**2)
      )
      theta_dot_dot = (term1 + term2) / self.j_term
  
      # Update everything appropriately
      self.t += dt
      self.x += dt * self.x_dot
      self.theta += dt * self.theta_dot
      self.x_dot += dt * x_dot_dot
      self.theta_dot += dt * theta_dot_dot
  
imports: from __future__ import division, print_function, absolute_import
  from vispy import app, visuals
  from vispy.visuals import transforms
  from vispy.io import load_data_file
  import sys
  import numpy
  import string
  import logging
  import traceback
  from PyQt5 import QtCore, QtGui, QtWidgets
label_desc: Use image node_id 6 for calling the WigglyBar obj's underlying member method code with example usage: obj._euler_update(dt) without return types