get_spectrum
Description:
[ Version ( since = "1.3.1" ) ]
public async Spectrum get_spectrum (SensorCap cap, Cancellable? cancellable) throws Error
  public async Spectrum get_spectrum (SensorCap cap, Cancellable? cancellable) throws Error
Gets a color spectrum from a sensor
Parameters:
| this | a Sensor instance. | 
| cap | |
| cancellable | a Cancellable, or null | 
| callback | the function to run on completion | 
| user_data | the data to pass to  |