atan2

Compute four-quadrant arctangent

  • Library:
  • Motor Control Blockset / Controls / Math Transforms

Description

The atan2 block performs the four-quadrant arctangent on two real numbers.

Equations

This equation describes how the block computes the four-quadrant arctangent (θ).

Theta=atan2(A,B)={arctan(AB)                 if B>0,arctan(AB)+π           if B<0 and A0,arctan(AB)π           if B<0 and A<0,+π2                            if B=0 and A>0, π2                            if B=0 and A<0,undefined                 if B=0 and A=0.

where:

π<Thetaπ    (Radians)

Ports

Input

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Real number on the y-axis that you provide as input to the block.

Data Types: single | double | fixed point

Real number on the x-axis that you provide as input to the block.

Data Types: single | double | fixed point

Output

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Angle represented by arctangent. This is the angle made by a vector from the origin to a specified point (x,y) with the positive x-axis.

Data Types: single | double | fixed point

The following figure shows the representation of input values A, B, and arctangent on the x-y coordinate plane.

Parameters

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Unit of the output values.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Fixed-Point Conversion
Design and simulate fixed-point systems using Fixed-Point Designer™.

Introduced in R2020a