code: def windspeed(self, t):
          
          ws = [0] * self.n
  
          for i in range(self.n):
              q = ceil(t / self.dt[i])
              q_prev = 0 if q == 0 else q - 1
  
              r = t % self.dt[i]
              r = 0 if abs(r) < 1e-6 else r
  
              if r == 0:
                  ws[i] = self.speed[i][q]
              else:
                  t1 = self.time[i][q_prev]
                  s1 = self.speed[i][q_prev]
                  s2 = self.speed[i][q]
                  ws[i] = s1 + (t - t1) * (s2 - s1) / self.dt[i]
  
          return matrix(ws)
docs: Return the wind speed list at time `t`