By default, floating-point numbers used in LabVIEW are double-precision (DBL). The old version of the function selection board only has plastic numerical constants, so it becomes double precision to put it into the program block diagram and directly input 0.0 or the required floating point number. You can also enter an integer and right-click "Represent", DBL. Version 20 1 1 began to add "DBL numerical constant".