fix_modify AtC on_the_fly <bond | kernel> <optional on | off> 
 - bond | kernel (keyword) = specifies on-the-fly calculation of bond or kernel matrix elements 
 fix_modify AtC on_the_fly bond on  
  fix_modify AtC on_the_fly kernel  
  fix_modify AtC on_the_fly kernel off  
 
Overrides normal mode of pre-calculating and storing bond pair-to-node a nd kernel atom-to-node matrices. If activated, will calculate elements of t hese matrices during repeated calls of field computations (i.e. "on-the-fly") and not store them for future use. 
 on flag is optional - if omitted, on_the_fly will be activated for the s pecified matrix. Can be deactivated using off flag. 
 
Must be used with the hardy/field type of AtC fix ( see fix atc command )
By default, on-the-fly calculation is not active (i.e. off). However, code does a memory allocation check to determine if it can store all needed bond and kernel matrix ele ments. If this allocation fails, on-the-fly is activated. 
 
 1.6.1
 1.6.1