title: differential equations BVP
body: <pre class="lang-py prettyprint-override"><code>#including the differential equations and parameters 
  
  def model(x,dydx,p): 
      s=p[0]  #first parameter 
      a=p[1]   #second parameter 
  
      dydx[0] = -2*(s+a)*y[0]+2*s*y[1]+s/2*y[2] 
      dydx[1] = +2*(s+a)*y[1]-2*s*y[0]-s/2*y[2] 
      dydx[2] = -(s+a)*y[2] 
  
      return np.vstack(dydx[0],dydx[1],dydx[2]) 
  
  # boundary conditions
  
  def bc(ya, yb,yc, p): 
      s=p[0]  
      a=p[1] 
      I0=1 
  
      return np.array(([ya[0], yb[0],yc[0],a,s])) 
  #x values 
  x = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9])   
  y = np.zeros((3, x.size)) 
  #p=  np.zeros((3, d.size)) 
  #y initial values 
  y[0]=3 
  y[1]=3 
  y[2]=2 
  
  I0 = 1 
  
  sol = solve_bvp(model, bc,x,y, p=[1,1]) 
  </code></pre>
  
  <p>I do not know how can I write the boundary conditions to solve the three differential equations</p>
  
  <p>I want to solve the equations and have the <code>y</code> values and parameters values </p>