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• ATAN

ATAN

Type	Function
Description	Calculates the principal arc tangent of the operand connected to IN1.
Parameters	Input IN1 Data type: ANY_REAL Description: Input value. Output OUT Data type: ANY_REAL Description: Output value in radians.
Error behavior	Error behavior The following table shows the errors which may occur while executing the function and the value returned by the function in the corresponding error case. As described, the value returned by the function in the error case depends on the value of the input (for example, if the input value is not a legal number (NaN), the function returns NaN). Error case Output value NaN NaN Inf+ π/2 Inf- -π/2
Additional information	EN/ENO behavior The POU is only executed if TRUE is applied to the EN input. If EN = FALSE, the POU is not executed and ENO = FALSE indicates the inactivity. If any of the errors listed under "Error behavior" occurs while executing the function, ENO is set to FALSE. Note ENO stays TRUE for an input value that is not a real number (NaN). Further Info See the topic "General information on execution control with EN/ENO" for further details.