A one zero filter. Implements the formula:
| in | 
 The input signal.  | 
| coef | 
 Feed forward coefficient. +0.5 makes a two point averaging filter (see also LPZ1 ). -0.5 makes a differentiator (see also HPZ1 ). +1 makes a single sample delay (see also Delay1 ). -1 makes an inverted single sample delay.  | 
| mul | 
 Output will be multiplied by this value.  | 
| add | 
 This value will be added to the output.  |