GVL_CM_Base

Limit value constants:

cCM_MinArgLog10 : LREAL :=  2.3E-308;   (* approximate minimum argument of decadic logarithm *)
cCM_MinArgLogN  : LREAL :=  2.3E-308;   (* approximate minimum argument of natural logarithm *)
cCM_MinArgDiv   : LREAL :=  2.3E-308;   (* minimum argument of division *)

The purpose of these constants is to avoid value range errors. The logarithm of real numbers is not defined in the case of negative numbers and zero. For this reason, constants are defined with values close to zero. The same applies to division by zero.

Constants for recommended overlapping:

cCM_OverlapRecommended  : UDINT := TO_UDINT(-1);    (* setting for recommended overlap (e.g. HannWindow: 50% overlapping) *)
cCM_OverlapInactive     : UDINT := TO_UDINT(-2);    (* setting in order to deactivate overlap *)

These constants are for setting the size of the internal data buffer when using the window functions. They serve in the InitPars structures of the respective function blocks as values for the parameter nOverlap.