rsspice 0.1.0

Pure Rust port of the SPICE Toolkit for space geometry
Documentation
//
// GENERATED FILE
//

use super::*;
use crate::SpiceContext;
use f2rust_std::*;

/// Matrix transpose times vector, general dimension
///
/// Multiply the transpose of a matrix and a vector of
/// arbitrary size.
///
/// # Brief I/O
///
/// ```text
///  VARIABLE  I/O  DESCRIPTION
///  --------  ---  --------------------------------------------------
///  M1         I   Left-hand matrix whose transpose is to be
///                 multiplied.
///  V2         I   Right-hand vector to be multiplied.
///  NC1        I   Column dimension of M1 and length of VOUT.
///  NR1R2      I   Row dimension of M1 and length of V2.
///  VOUT       O   Product vector M1**T * V2.
/// ```
///
/// # Detailed Input
///
/// ```text
///  M1       is a double precision matrix of arbitrary size whose
///           transpose forms the left-hand matrix of the
///           multiplication.
///
///  V2       is a double precision vector on the right of the
///           multiplication.
///
///  NC1      is the column dimension of M1 and length of VOUT.
///
///  NR1R2    is the row dimension of M1 and length of V2.
/// ```
///
/// # Detailed Output
///
/// ```text
///  VOUT     is the double precision vector which results from
///           the expression
///
///                         T
///              VOUT = (M1)  x V2
///
///           where the T denotes the transpose of M1.
///
///           VOUT must NOT overwrite either M1 or V2.
/// ```
///
/// # Exceptions
///
/// ```text
///  Error free.
/// ```
///
/// # Particulars
///
/// ```text
///  The code reflects precisely the following mathematical expression
///
///  For each value of the subscript I from 1 to NC1,
///
///  VOUT(I) = Summation from K=1 to NR1R2 of  ( M1(K,I) * V2(K) )
///
///  Note that the reversal of the K and I subscripts in the left-hand
///  matrix M1 is what makes VOUT the product of the TRANSPOSE of M1
///  and not simply of M1 itself.
///
///  Since this subroutine operates on matrices of arbitrary size, it
///  is not feasible to buffer intermediate results. Thus, VOUT
///  should NOT overwrite either M1 or V2.
/// ```
///
/// # 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) Given a 3x2 matrix and a 3-vector, multiply the transpose of
///     the matrix by the vector.
///
///
///     Example code begins here.
///
///
///           PROGRAM MTXVG_EX1
///           IMPLICIT NONE
///
///     C
///     C     Local variables.
///     C
///           DOUBLE PRECISION      M    ( 3, 2 )
///           DOUBLE PRECISION      VIN  ( 3    )
///           DOUBLE PRECISION      VOUT ( 2    )
///
///           INTEGER               I
///           INTEGER               J
///
///     C
///     C     Define M and VIN.
///     C
///           DATA                  M    /  1.0D0,  1.0D0,  1.0D0,
///          .                              2.0D0,  3.0D0,  4.0D0  /
///
///           DATA                  VIN  /  1.0D0,  2.0D0,  3.0D0  /
///
///     C
///     C     Multiply the transpose of M by VIN.
///     C
///           CALL MTXVG ( M, VIN, 2, 3, VOUT )
///
///           WRITE(*,'(A)') 'Transpose of M times VIN:'
///           WRITE(*,'(2F10.3)') VOUT
///
///           END
///
///
///     When this program was executed on a Mac/Intel/gfortran/64-bit
///     platform, the output was:
///
///
///     Transpose of M times VIN:
///          6.000    20.000
/// ```
///
/// # Restrictions
///
/// ```text
///  1)  The user is responsible for checking the magnitudes of the
///      elements of M1 and V2 so that a floating point overflow does
///      not occur.
///
///  2)  VOUT not overwrite M1 or V2 or else the intermediate
///      will affect the final result.
/// ```
///
/// # Author and Institution
///
/// ```text
///  J. Diaz del Rio    (ODC Space)
///  W.M. Owen          (JPL)
///  W.L. Taber         (JPL)
/// ```
///
/// # Version
///
/// ```text
/// -    SPICELIB Version 1.1.0, 04-JUL-2021 (JDR)
///
///         Added IMPLICIT NONE statement.
///
///         Edited the header to comply with NAIF standard.
///         Added complete code example based on the existing 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 (WMO)
/// ```
pub fn mtxvg(m1: &[f64], v2: &[f64], nc1: i32, nr1r2: i32, vout: &mut [f64]) {
    MTXVG(m1, v2, nc1, nr1r2, vout);
}

//$Procedure MTXVG ( Matrix transpose times vector, general dimension )
pub fn MTXVG(M1: &[f64], V2: &[f64], NC1: i32, NR1R2: i32, VOUT: &mut [f64]) {
    let M1 = DummyArray2D::new(M1, 1..=NR1R2, 1..=NC1);
    let V2 = DummyArray::new(V2, 1..=NR1R2);
    let mut VOUT = DummyArrayMut::new(VOUT, 1..=NC1);
    let mut SUM: f64 = 0.0;

    //
    // Local variables
    //

    //
    // Perform the matrix-vector multiplication
    //
    for I in 1..=NC1 {
        SUM = 0.0;

        for K in 1..=NR1R2 {
            SUM = (SUM + (M1[[K, I]] * V2[K]));
        }

        VOUT[I] = SUM;
    }
}