code: def dewpoint_temperature(temp, hum):
      
      assert(temp.shape == hum.shape)
  
      vap_press = vapor_pressure(temp, hum)
  
      positives = np.array(temp >= 273.15)
      dewpoint_temp = temp.copy() * np.nan
      dewpoint_temp[positives] = 243.12 * np.log(vap_press[positives] / 6.112) / (17.62 - np.log(vap_press[positives] / 6.112))
      dewpoint_temp[~positives] = 272.62 * np.log(vap_press[~positives] / 6.112) / (22.46 - np.log(vap_press[~positives] / 6.112))
  
      return dewpoint_temp + 273.15
docs: computes the dewpoint temperature
  
      Parameters
      ----
      temp :      temperature [K]
      hum :       relative humidity
      
  
      Returns
          dewpoint temperature in K