# Atan

```block Atan "Output the arc tangent of the input"
equation
y = Modelica.Math.atan(u);

annotation (
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Documentation(info = "<html>\n<p>\nThis blocks computes the output <strong>y</strong> as the\n<em>tangent-inverse</em> of the input <strong>u</strong>:\n</p>\n<pre>\n    y= <strong>atan</strong>( u );\n</pre>\n\n<p>\n<img src=\"modelica://Modelica/Resources/Images/Math/atan.png\"\n     alt=\"atan.png\">\n</p>\n\n</html>"));
end Atan;

```