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//
// GENERATED FILE
//
use super::*;
use crate::SpiceContext;
use f2rust_std::*;
/// Vector cross product, 3 dimensions
///
/// Compute the cross product of two 3-dimensional vectors.
///
/// # Brief I/O
///
/// ```text
/// VARIABLE I/O DESCRIPTION
/// -------- --- --------------------------------------------------
/// V1 I Left hand vector for cross product.
/// V2 I Right hand vector for cross product.
/// VOUT O Cross product V1 x V2.
/// ```
///
/// # Detailed Input
///
/// ```text
/// V1,
/// V2 are two 3-dimensional vectors. Typically, these might
/// represent the (possibly unit) vector to a planet, Sun,
/// or a star which defines the orientation of axes of some
/// reference frame.
/// ```
///
/// # Detailed Output
///
/// ```text
/// VOUT is the cross product of V1 and V2.
/// ```
///
/// # Exceptions
///
/// ```text
/// Error free.
/// ```
///
/// # Particulars
///
/// ```text
/// VCRSS calculates the three dimensional cross product of two
/// vectors according to the definition.
///
/// If V1 and V2 are large in magnitude (taken together, their
/// magnitude surpasses the limit allowed by the computer) then it
/// may be possible to generate a floating point overflow from an
/// intermediate computation even though the actual cross product may
/// be well within the range of double precision numbers. VCRSS does
/// NOT check the magnitude of V1 or V2 to insure that overflow will
/// not occur.
/// ```
///
/// # Examples
///
/// ```text
/// The numerical results shown for this example may differ across
/// platforms. The results depend on the SPICE kernels used as
/// input, the compiler and supporting libraries, and the machine
/// specific arithmetic implementation.
///
/// 1) Define two sets of vectors and compute the cross product of
/// each vector in first set and the corresponding vector in
/// the second set.
///
///
/// Example code begins here.
///
///
/// PROGRAM VCRSS_EX1
/// IMPLICIT NONE
///
/// C
/// C Local parameters.
/// C
/// INTEGER NDIM
/// PARAMETER ( NDIM = 3 )
///
/// INTEGER SETSIZ
/// PARAMETER ( SETSIZ = 2 )
///
/// C
/// C Local variables.
/// C
/// DOUBLE PRECISION SETA ( NDIM, SETSIZ )
/// DOUBLE PRECISION SETB ( NDIM, SETSIZ )
/// DOUBLE PRECISION VOUT ( NDIM )
///
/// INTEGER I
/// INTEGER J
///
/// C
/// C Define the two vector sets.
/// C
/// DATA SETA / 0.D0, 1.D0, 0.D0,
/// . 5.D0, 5.D0, 5.D0 /
///
/// DATA SETB / 1.D0, 0.D0, 0.D0,
/// . -1.D0, -1.D0, -1.D0 /
///
/// C
/// C Calculate the cross product of each pair of vectors
/// C
/// DO I=1, SETSIZ
///
/// CALL VCRSS ( SETA(1,I), SETB(1,I), VOUT )
///
/// WRITE(*,'(A,3F5.1)') 'Vector A : ',
/// . ( SETA(J,I), J=1,3 )
/// WRITE(*,'(A,3F5.1)') 'Vector B : ',
/// . ( SETB(J,I), J=1,3 )
/// WRITE(*,'(A,3F5.1)') 'Cross product: ', VOUT
/// WRITE(*,*) ' '
///
/// END DO
///
/// END
///
///
/// When this program was executed on a Mac/Intel/gfortran/64-bit
/// platform, the output was:
///
///
/// Vector A : 0.0 1.0 0.0
/// Vector B : 1.0 0.0 0.0
/// Cross product: 0.0 0.0 -1.0
///
/// Vector A : 5.0 5.0 5.0
/// Vector B : -1.0 -1.0 -1.0
/// Cross product: 0.0 0.0 0.0
/// ```
///
/// # Restrictions
///
/// ```text
/// 1) No checking of V1 or V2 is done to prevent floating point
/// overflow. The user is required to determine that the
/// magnitude of each component of the vectors is within an
/// appropriate range so as not to cause floating point overflow.
/// In almost every case there will be no problem and no checking
/// actually needs to be done.
/// ```
///
/// # Author and Institution
///
/// ```text
/// N.J. Bachman (JPL)
/// J. Diaz del Rio (ODC Space)
/// W.M. Owen (JPL)
/// W.L. Taber (JPL)
/// ```
///
/// # Version
///
/// ```text
/// - SPICELIB Version 1.1.0, 05-JUL-2021 (JDR)
///
/// Added IMPLICIT NONE statement.
///
/// Edited the header to comply with NAIF standard. Added complete
/// code example based on existing example.
///
/// - SPICELIB Version 1.0.2, 22-APR-2010 (NJB)
///
/// Header correction: assertions that the output
/// can overwrite the input have been removed.
///
/// - SPICELIB Version 1.0.1, 10-MAR-1992 (WLT)
///
/// Comment section for permuted index source lines was added
/// following the header.
///
/// - SPICELIB Version 1.0.0, 31-JAN-1990 (WMO)
/// ```
pub fn vcrss(v1: &[f64; 3], v2: &[f64; 3], vout: &mut [f64; 3]) {
VCRSS(v1, v2, vout);
}
//$Procedure VCRSS ( Vector cross product, 3 dimensions )
pub fn VCRSS(V1: &[f64], V2: &[f64], VOUT: &mut [f64]) {
let V1 = DummyArray::new(V1, 1..=3);
let V2 = DummyArray::new(V2, 1..=3);
let mut VOUT = DummyArrayMut::new(VOUT, 1..=3);
let mut VTEMP = StackArray::<f64, 3>::new(1..=3);
//
// Local variables
//
//
// Calculate the cross product of V1 and V2, store in VTEMP
//
VTEMP[1] = ((V1[2] * V2[3]) - (V1[3] * V2[2]));
VTEMP[2] = ((V1[3] * V2[1]) - (V1[1] * V2[3]));
VTEMP[3] = ((V1[1] * V2[2]) - (V1[2] * V2[1]));
//
// Now move the result into VOUT
//
VOUT[1] = VTEMP[1];
VOUT[2] = VTEMP[2];
VOUT[3] = VTEMP[3];
//
}