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//
// GENERATED FILE
//
use super::*;
use crate::SpiceContext;
use f2rust_std::*;
/// Vector linear combination, 3 dimensions
///
/// Compute a vector linear combination of two double precision,
/// 3-dimensional vectors.
///
/// # Brief I/O
///
/// ```text
/// VARIABLE I/O DESCRIPTION
/// -------- --- --------------------------------------------------
/// A I Coefficient of V1.
/// V1 I Vector in 3-space.
/// B I Coefficient of V2.
/// V2 I Vector in 3-space.
/// SUM O Linear vector combination A*V1 + B*V2.
/// ```
///
/// # Detailed Input
///
/// ```text
/// A is the double precision scalar variable that multiplies
/// V1.
///
/// V1 is an arbitrary, double precision 3-dimensional vector.
///
/// B is the double precision scalar variable that multiplies
/// V2.
///
/// V2 is an arbitrary, double precision 3-dimensional vector.
/// ```
///
/// # Detailed Output
///
/// ```text
/// SUM is the double precision 3-dimensional vector which
/// contains the linear combination
///
/// A * V1 + B * V2
/// ```
///
/// # Exceptions
///
/// ```text
/// Error free.
/// ```
///
/// # Particulars
///
/// ```text
/// The code reflects precisely the following mathematical expression
///
/// For each value of the index I, from 1 to 3:
///
/// SUM(I) = A * V1(I) + B * V2(I)
///
/// No error checking is performed to guard against numeric overflow.
/// ```
///
/// # Examples
///
/// ```text
/// The numerical results shown for these examples 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) Suppose you want to generate a sequence of points representing
/// an elliptical footprint, from the known semi-major
/// and semi-minor axes.
///
///
/// Example code begins here.
///
///
/// PROGRAM VLCOM_EX1
/// IMPLICIT NONE
///
/// C
/// C SPICELIB functions.
/// C
/// DOUBLE PRECISION TWOPI
///
/// C
/// C Local parameters.
/// C
///
/// C
/// C Local variables.
/// C
/// DOUBLE PRECISION STEP
/// DOUBLE PRECISION THETA
/// DOUBLE PRECISION SMAJOR ( 3 )
/// DOUBLE PRECISION SMINOR ( 3 )
/// DOUBLE PRECISION VECTOR ( 3 )
///
/// INTEGER I
///
/// C
/// C Let SMAJOR and SMINOR be the two known semi-major and
/// C semi-minor axes of our elliptical footprint.
/// C
/// DATA SMAJOR /
/// . 0.070115D0, 0.D0, 0.D0 /
///
/// DATA SMINOR /
/// . 0.D0, 0.035014D0, 0.D0 /
///
///
/// C
/// C Compute the vectors of interest and display them
/// C
/// THETA = 0.D0
/// STEP = TWOPI() / 16
///
/// DO I = 1, 16
///
/// CALL VLCOM ( COS(THETA), SMAJOR,
/// . SIN(THETA), SMINOR, VECTOR )
///
/// WRITE(*,'(I2,A,3F10.6)') I, ':', VECTOR
///
/// THETA = THETA + STEP
///
/// END DO
///
/// END
///
///
/// When this program was executed on a Mac/Intel/gfortran/64-bit
/// platform, the output was:
///
///
/// 1: 0.070115 0.000000 0.000000
/// 2: 0.064778 0.013399 0.000000
/// 3: 0.049579 0.024759 0.000000
/// 4: 0.026832 0.032349 0.000000
/// 5: 0.000000 0.035014 0.000000
/// 6: -0.026832 0.032349 0.000000
/// 7: -0.049579 0.024759 0.000000
/// 8: -0.064778 0.013399 0.000000
/// 9: -0.070115 0.000000 0.000000
/// 10: -0.064778 -0.013399 -0.000000
/// 11: -0.049579 -0.024759 -0.000000
/// 12: -0.026832 -0.032349 -0.000000
/// 13: -0.000000 -0.035014 -0.000000
/// 14: 0.026832 -0.032349 0.000000
/// 15: 0.049579 -0.024759 0.000000
/// 16: 0.064778 -0.013399 0.000000
///
///
/// 2) As a second example, suppose that U and V are orthonormal
/// vectors that form a basis of a plane. Moreover suppose that we
/// wish to project a vector X onto this plane.
///
///
/// Example code begins here.
///
///
/// PROGRAM VLCOM_EX2
/// IMPLICIT NONE
///
/// C
/// C SPICELIB functions.
/// C
/// DOUBLE PRECISION VDOT
///
/// C
/// C Local variables.
/// C
/// DOUBLE PRECISION PUV ( 3 )
/// DOUBLE PRECISION X ( 3 )
/// DOUBLE PRECISION U ( 3 )
/// DOUBLE PRECISION V ( 3 )
///
/// C
/// C Let X be an arbitrary 3-vector
/// C
/// DATA X / 4.D0, 35.D0, -5.D0 /
///
/// C
/// C Let U and V be orthonormal 3-vectors spanning the
/// C plane of interest.
/// C
/// DATA U / 0.D0, 0.D0, 1.D0 /
///
/// V(1) = SQRT(2.D0)/2.D0
/// V(2) = -SQRT(2.D0)/2.D0
/// V(3) = 0.D0
///
/// C
/// C Compute the projection of X onto this 2-dimensional
/// C plane in 3-space.
/// C
/// CALL VLCOM ( VDOT ( X, U ), U, VDOT ( X, V ), V, PUV )
///
/// C
/// C Display the results.
/// C
/// WRITE(*,'(A,3F6.1)') 'Input vector : ', X
/// WRITE(*,'(A,3F6.1)') 'Projection into 2-d plane: ', PUV
///
/// END
///
///
/// When this program was executed on a Mac/Intel/gfortran/64-bit
/// platform, the output was:
///
///
/// Input vector : 4.0 35.0 -5.0
/// Projection into 2-d plane: -15.5 15.5 -5.0
/// ```
///
/// # Restrictions
///
/// ```text
/// 1) No error checking is performed to guard against numeric
/// overflow or underflow. The user is responsible for insuring
/// that the input values are reasonable.
/// ```
///
/// # Author and Institution
///
/// ```text
/// J. Diaz del Rio (ODC Space)
/// W.L. Taber (JPL)
/// ```
///
/// # Version
///
/// ```text
/// - SPICELIB Version 1.1.0, 13-AUG-2021 (JDR)
///
/// Added IMPLICIT NONE statement.
///
/// Edited the header to comply with NAIF standard. Removed
/// unnecessary $Revisions section.
///
/// Added complete code example.
///
/// - SPICELIB Version 1.0.1, 10-MAR-1992 (WLT)
///
/// Comment section for permuted index source lines was added
/// following the header.
///
/// - SPICELIB Version 1.0.0, 31-JAN-1990 (WLT)
/// ```
pub fn vlcom(a: f64, v1: &[f64; 3], b: f64, v2: &[f64; 3], sum: &mut [f64; 3]) {
VLCOM(a, v1, b, v2, sum);
}
//$Procedure VLCOM ( Vector linear combination, 3 dimensions )
pub fn VLCOM(A: f64, V1: &[f64], B: f64, V2: &[f64], SUM: &mut [f64]) {
let V1 = DummyArray::new(V1, 1..=3);
let V2 = DummyArray::new(V2, 1..=3);
let mut SUM = DummyArrayMut::new(SUM, 1..=3);
SUM[1] = ((A * V1[1]) + (B * V2[1]));
SUM[2] = ((A * V1[2]) + (B * V2[2]));
SUM[3] = ((A * V1[3]) + (B * V2[3]));
}