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Short helpfile for action ZANGLES
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The input trajectory can be in any of the following formats: 

                  ATOMS - the pairs of atoms that you would like to calculate the 
                          angles for. You can use multiple instances of this keyword i.e. 
                          ATOMS1, ATOMS2, ATOMS3... 

The following options are available

                HIGHEST - ( default=off ) this flag allows you to recover the highest 
                          of these variables. 
                 LOWEST - ( default=off ) this flag allows you to recover the lowest 
                          of these variables. 
                    SUM - ( default=off ) calculate the sum of all the quantities. 
                   MEAN - ( default=off ) calculate the mean of all the quantities. 
              LESS_THAN - calculate the number of variables that are less than a 
                          certain target value. 
              MORE_THAN - calculate the number of variables that are more than a 
                          certain target value. 
                ALT_MIN - calculate the minimum value. 
                    MIN - calculate the minimum value. 
                    MAX - calculate the maximum value. 
                BETWEEN - calculate the number of values that are within a certain 
                          range. These quantities are calculated using kernel density 
                          estimation as described on \ref histogrambead.. You can use multiple 
                          instances of this keyword i.e. BETWEEN1, BETWEEN2, BETWEEN3... 
              HISTOGRAM - calculate a discretized histogram of the distribution of 
                          values. This shortcut allows you to calculates NBIN quantites like 
                          BETWEEN. 


