Version Information
Release Notes, Update information, Certifications and Frequently Asked Questions.
Concepts
Your first step into modern and powerful process visualization.
Deployment
Topics, you need to know, before using WinCC OA.
Security
Go beyond the norm in cybersecurity.
Engineering
Powerful tools for easy or complex engineering tasks.
Data Management
Classify, structure and archive your data.
Business Logic / Control
Endless possibilities in data processing for your projects.
- Introduction to CTRL
  An introduction to the product's own programming language Control(CTRL).
- Control Classes
  The overview of classes available in Control.
- Types of Control Functions
  An overview of the types of functions distinguished within Control.
- Control graphics
- CONTROL Functions
  - Funtions A
    - abortFileTransfer()
      The function abortFileTransfer() aborts all file transfers of the stated manager.
    - abs()
      Returns the absolute value of a value.
    - access()
      Queries the access mode of the file or directory with the specified path name.
    - acGetRefACType()
      Returns a AC type name, if the leaf dpeName is referenced to an AC type, otherwise an empty string.
    - acos()
      Returns the arc cosine in the radian measure.
    - activateMode()
      Switches the module to normal operating mode.
    - addGlobal()
      Creates a variable and makes it into a control-wide variable.
    - addGroup()
      Adds a group of shapes or a layout to a panel.
    - addGroupPVSS()
      Adds a user group of an external authentication system to the WinCC OA user administration.
    - addShape()
      Adds a new shape into a panel.
    - addSymbol()
      Adds a panel reference in a panel or layout at a later time during run time. To suppress the Initialize scripts of the reference the function createSymbol() can be used instead.
    - addUserPVSS()
      Adds a user of an external authentication system to the WinCC OA user administration.
    - addUserToGroupPVSS()
      Adds a WinCC OA user to a user group in the WinCC OA user administration.
    - aes256Decrypt()
      The function allows to decrypt an encrypted information with the AES-256 algorithm.
    - aes256Encrypt()
      The function allows to encrypt the passed information with the AES-256 algorithm.
    - afterLogin()
      After successful login displays the required panel.
    - alertConnect()
      Registers the function work() for call with resulting alerts.
    - alertDisconnect()
      Unregisters the function work() from call when changes are made to the values.
    - alertGet()
      Queries only the last alert attributes of a data point.
    - alertGetPeriod()
      Reads the values of the specified alert attributes of the data point elements for which alerts were triggered.
    - alertSet()
      Allows data point attributes to be set in a similar way to dpSet().
    - alertSetTimed()
      Allows data point attributes to be set in a similar way to dpSet(). Additionally the timestamp can be set manually.
    - alertSetTimedWait()
      Allows data point attributes to be set in a similar way to dpSet(). Additionally the timestamp can be set manually.
    - alertSetWait()
      Allows data point attributes to be set in a similar way to alertSet()/dpSetWait().
    - animate()
      With the function animate() you can create animations.
    - animateWait()
      With the function animateWait() you can create animations and wait for them to finish.
    - asin()
      Returns the arc sine in the radian measure.
    - assignPtr()
      The function allows to assign a shared_ptr to a different shared_ptr..
    - atan()
      Returns the arc tangent in the radian measure.
    - atan2()
      Returns the arc tangent of the Cartesian coordinates y and x.
    - "availableCameras"
      This function shows the cameras available on the system.
  - Funtions B
  - Funtions C
  - Funtions D
  - Functions E
  - Functions F
  - Functions G
  - Functions H
  - Functions I
  - Functions J
  - Functions K
  - Functions L
  - Functions M
  - Functions N
  - Functions O
  - Functions P
  - Functions Q
  - Functions R
  - Functions S
  - Functions T
  - Functions U
  - Functions V
  - Functions W
  - Functions X
  - Functions Y
  - Functions Z
- CtrlExtension
  The CtrlExtension allows the addition of custom C++ code.
- CTRL Debugger
  You can use the CTRL debugger to debug the Control programming language. The debugger can be used via its own panel, which also enables the monitoring and setting of variable values during the execution of a script.
- SQL in CONTROL
  The database functions enable you to quickly carry out value queries on data points and elements.
- API Manager
  The WinCC OA API (Application Programming Interface) offers a number of functions adding special Managers to this process control system.
Data Visualization
User interfaces, Trends and Reports for every purpose and device.
Southbound Interfaces
The process connection to the actual machines/sensors.
Northbound Interfaces
Your portal to the cloud or supervising systems.
Web Connectivity / Network Interfaces
Data exchange, APIs and web technologies
User Management
All about authorization, authentication and login-customization.
Availability
How to get your system uptime to the maximum.
Reporting
Create state of the art project reports without limits.
Addons
Useful tools and enhancements for special demands.
Reference Tables
Detailed and extensive content for special project adaptation.
Videos & Tutorials
Explore the capabilities of WinCC OA with our carefully selected collection of video tutorials and guides.
WinCC OA Documentation
Basic information about terms and functions within the documentation.
Disclaimer
A brief clarification of liability exclusions or legal notices.

atan()

Returns the arc tangent in the radian measure.

Synopsis

float atan(float x);

Parameters


Parameter	Description
x	angle

Return Value

Arc tangent in radian measure.

Description

Returns the arc tangent between -Pi/2 and Pi/2 in the radian measure. In the event of an error, 0.0 is returned.

Example

main()
{
  float pi = 3.1415926, val, res;
  val = 2.0;
  res = atan(param) * 180 / pi;
  DebugN("The atan for a value of " + val + " is " + res);
  //["The atan for a value of 2 is 63.434949905006"]
}

Assignment

Mathematical function

Availability

CTRL