log / logL

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Function A function calculates a result according to the current value of its inputs. A function has no internal data and is not linked to declared instances. - Calculates the logarithm (base 10) of the input.

Inputs

Input	Data Type	Range	Unit	Default	Description
IN	REAL / LREAL				Real value.

Outputs

Output	Data Type	Range	Unit	Description
Q	REAL / LREAL			Result: Logarithm (base 10) of IN.

Remarks

None

FBD Language Example

LogFbd.gif (1149 octets)

FFLD Language Example

In the FFLD "Free Form Ladder Diagram" Language, the operation is executed only if the input rung (EN) is TRUE.
- The output rung (ENO) keeps the same value as the input rung.
- The function is executed only if EN is TRUE.
- ENO has the same value as EN.

IL Language Example

In the IL "Instruction List" This is a low-level language and resembles assembly Language, the first input must be loaded before the function call.

Op1: LD "Ladder diagram"
Ladder logic is a method of drawing electrical logic schematics. It is now a very popular graphical language for programming Programmable Logic Controllers (PLCs). It was originally invented to describe logic made from relays. The name is based on the observation that programs in this language resemble ladders, with two vertical "rails" and a series of horizontal "rungs" between them  IN
     LOG
     ST  Q    (* Q is: LOG (IN) *)

ST Language Example

Q := LOG (IN);