# Q2EV: Convert from rotation Quaternions to Euler Vectors In RSpincalc: Conversion Between Attitude Representations of DCM, Euler Angles, Quaternions, and Euler Vectors

## Description

`Q2EV` converts from Quaternions (Q) to Euler Vectors (EV).

## Usage

 `1` ```Q2EV(Q, tol = 10 * .Machine\$double.eps, ichk = FALSE, ignoreAllChk = FALSE) ```

## Arguments

 `Q` Quaternion (Q) vector [q1, q2, q3, q4]. `tol` Tolerance from deviations from unity for the determinant of rotation matrices or the the vector length for unitary vectors. `ichk` Logical, FALSE=disables near-singularity warnings. `ignoreAllChk` Logical, TRUE=disables all warnings and error checks (use with caution!).

## Value

Euler Vectors (EV) vector [m1, m2, m3, MU].

Jose Gama

## References

by John Fuller, 14 Jul 2008 SpinCalc, Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors. http://www.mathworks.com/matlabcentral/fileexchange/20696-function-to-convert-between-dcm–euler-angles–quaternions–and-euler-vectors

Paolo de Leva, 01 May 2013 SpinConv, Conversion from a rotation representation type to another. http://www.mathworks.com/matlabcentral/fileexchange/41562-spinconv

`EV2Q`

## Examples

 ```1 2``` ```Q <- c(-0.1677489, -0.7369231, -0.3682588, 0.5414703) Q2EV(Q) ```

### Example output

```          [,1]      [,2]      [,3]     [,4]
[1,] 0.1995301 0.8765382 0.4380279 4.285963
```

RSpincalc documentation built on May 2, 2019, 10:59 a.m.