Provides MATLAB Coder helper functions to calculate the Euclidean norm of a vector. More...

#include "rtwtypes.h"
#include <stddef.h>
#include <stdlib.h>

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Functions
double	b_norm (const double x[3])
	Calculates the Euclidean norm (magnitude) of a 3-element vector.

double	c_norm (const double x[4])
	Calculates the Euclidean norm (magnitude) of a 4-element vector.

Detailed Description

Provides MATLAB Coder helper functions to calculate the Euclidean norm of a vector.

Author: Francesco Abate, MSA (Originally generated by MATLAB Coder)

Version: 24.2 (MATLAB Coder version)

Date: 2025-05-05

This auto-generated helper file from MATLAB Coder provides C equivalents of MATLAB's norm() command. The functions calculate the Euclidean norm (also known as the L2-norm) of a vector, which corresponds to its magnitude or length.

The formula used is: $\sqrt{\sum_{i=1}^{n} x_i^2}$

These functions are used as low-level utilities within more complex control algorithms, such as the MEKF, for vector operations.

Definition in file norm.h.

Function Documentation

◆ b_norm()

double b_norm ( const double x[3] )

Calculates the Euclidean norm (magnitude) of a 3-element vector.

Parameters

[in] x A 3-element array representing the input vector.

Returns: The Euclidean norm of the vector as a double.

Definition at line 21 of file norm.c.

{
  double absxk;
  double scale;
  double t;
  double y;
  scale = 3.3121686421112381E-170;
  absxk = fabs(x[0]);
  if (absxk > 3.3121686421112381E-170) {
    y = 1.0;
    scale = absxk;
  } else {
    t = absxk / 3.3121686421112381E-170;
    y = t * t;
  }
  absxk = fabs(x[1]);
  if (absxk > scale) {
    t = scale / absxk;
    y = y * t * t + 1.0;
    scale = absxk;
  } else {
    t = absxk / scale;
    y += t * t;
  }
  absxk = fabs(x[2]);
  if (absxk > scale) {
    t = scale / absxk;
    y = y * t * t + 1.0;
    scale = absxk;
  } else {
    t = absxk / scale;
    y += t * t;
  }
  return scale * sqrt(y);
}

Referenced by mekf().

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◆ c_norm()

double c_norm ( const double x[4] )

Calculates the Euclidean norm (magnitude) of a 4-element vector.