Short summary

Name	`TRUNC`
→POU type	→function
Category	IEC-block, ConvertEnh
Conform to →IEC-standard	not defined in IEC-standard
Graphical interface
Available since	version 1.27.0 (for logi.CAD 3) version 3.1.0 (for library `Standard`) – For inputs of data type `REAL`, the optimized `float` variant of the C-runtime is used. Compared to previous versions , it is possible that (marginal) other results are returned within the threshold range of the block.

Functionality

The mathematical function trunc is called:

The decimal portion of the floating-point number connected to input IN is truncated (there is no rounding). The block returns the integer value as a REAL or LREAL value.

Compare: TRUNC blocks according to IEC-standard (listed under "Convert").

Inputs, return value

	Identifier	→Data type	Description
Inputs:	`IN`	`REAL`, `LREAL` (corresponds to →generic data type `ANY_REAL`)	value to truncate
Return value:	–	`REAL`, `LREAL` (corresponds to →generic data type `ANY_REAL`)

Input EN and output ENO are available when →calling the block. See "Execution control: EN, ENO" for information on input EN and output ENO.

Example for usage within ST-editor

PROGRAM Test
   VAR
      result1, result2, result3, result4, result5, result6, result7, result8 : REAL;
   END_VAR
   result1 := TRUNC(2.8);     (* The variable 'result1' evaluates to '2.0'. *)
   result2 := TRUNC(2.5);     (* The variable 'result2' evaluates to '2.0'. *)
   result3 := TRUNC(2.01);    (* The variable 'result3' evaluates to '2.0'. *)
   result4 := TRUNC(2.0);     (* The variable 'result4' evaluates to '2.0'. *)
  
   result5 := TRUNC(-2.0);    (* The variable 'result5' evaluates to '-2.0'. *)
   result6 := TRUNC(-2.3);    (* The variable 'result6' evaluates to '-2.0'. *)
   result7 := TRUNC(-2.5);    (* The variable 'result7' evaluates to '-2.0'. *)
   result8 := TRUNC(-2.99);   (* The variable 'result8' evaluates to '-2.0'. *)
END_PROGRAM

When creating your application within the ST-editor, enter a call of a block by typing the text as requested by the syntax or use Content Assist.