OpenBLAS/lapack/trti2/ztrti2_L.c

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#include <stdio.h>
#include "common.h"

#ifdef UNIT
#define ZTRMV	ZTRMV_NLU
#else
#define ZTRMV	ZTRMV_NLN
#endif

blasint CNAME(blas_arg_t *args, BLASLONG *range_m, BLASLONG *range_n, FLOAT *sa, FLOAT *sb, BLASLONG myid) {

  BLASLONG  n, lda;
  FLOAT *a;

  FLOAT ajj_r, ajj_i;
#ifndef UNIT
  FLOAT ratio, den;
#endif
  BLASLONG j;

  n      = args -> n;
  a      = (FLOAT *)args -> a;
  lda    = args -> lda;

  if (range_n) {
    n      = range_n[1] - range_n[0];
    a     += range_n[0] * (lda + 1) * COMPSIZE;
  }

  for (j = n - 1; j >= 0; j--) {


#ifndef UNIT
    ajj_r = *(a + (j + j * lda) * COMPSIZE + 0);
    ajj_i = *(a + (j + j * lda) * COMPSIZE + 1);

  if (fabs(ajj_r) >= fabs(ajj_i)){
    ratio = ajj_i / ajj_r;
    den   = 1. / (ajj_r * ( 1 + ratio * ratio));
    ajj_r =  den;
    ajj_i = -ratio * den;
  } else {
    ratio = ajj_r / ajj_i;
    den   = 1. /(ajj_i * ( 1 + ratio * ratio));
    ajj_r =  ratio * den;
    ajj_i = -den;
  }

  *(a + (j + j * lda) * COMPSIZE + 0) = ajj_r;
  *(a + (j + j * lda) * COMPSIZE + 1) = ajj_i;
#else
    ajj_r =  ONE;
    ajj_i =  ZERO;
#endif

  ZTRMV (n - j - 1,
	 a + ((j + 1) + (j + 1) * lda) * COMPSIZE, lda,
	 a + ((j + 1) + j * lda) * COMPSIZE, 1,
	 sb);

  SCAL_K(n - j - 1, 0, 0,
	  -ajj_r, -ajj_i,
	  a + ((j + 1)  + j * lda) * COMPSIZE, 1,
	  NULL, 0, NULL, 0);
  }

  return 0;
}