void compute_temp(double *power, double *temp, int n_units, double time_elapsed)
{
int i;
double *pow, h, n_iter;
pow = vector(NL*n_units+EXTRA);
/* set power numbers for the virtual nodes */
set_internal_power(power, n_units);
/* find (inv_A)*POWER */
matvectmult(pow, inva, power, NL*n_units+EXTRA);
/* step size for 4th-order Runge-Kutta - assume worst case */
h = PRECISION / max_slope;
n_iter = time_elapsed / h;
n_iter = (n_iter > MIN_ITER) ? n_iter : MIN_ITER; /* do at least MIN_ITER iterations */
h = time_elapsed / n_iter;
if (n_iter >= TOO_LONG)
fprintf(stderr, "warning: calling interval too large, performing %.0f iterations - it may take REALLY long\n", n_iter);
/* Obtain temp at time (t+h).
* Instead of getting the temperature at t+h directly, we do it
* in n_iter steps to reduce the error due to rk4
*/
for (i = 0; i < n_iter; i++)
rk4(c, temp, pow, NL*n_units+EXTRA, h, temp);
free_vector(pow);
}
/* compute the slope vector dy for the transient equation
* dy + cy = p. useful in the transient solver
*/
void slope_fn_block(block_model_t *model, double *y, double *p, double *dy)
{
/* shortcuts */
int n = model->n_nodes;
double **c = model->c;
/* for our equation, dy = p - cy */
#if (MATHACCEL == MA_INTEL || MATHACCEL == MA_APPLE)
/* dy = p */
cblas_dcopy(n, p, 1, dy, 1);
/* dy = dy - c*y = p - c*y */
cblas_dgemv(CblasRowMajor, CblasNoTrans, n, n, -1, c[0],
n, y, 1, 1, dy, 1);
#elif (MATHACCEL == MA_AMD || MATHACCEL == MA_SUN)
/* dy = p */
dcopy(n, p, 1, dy, 1);
/* dy = dy - c*y = p - c*y */
dgemv('T', n, n, -1, c[0], n, y, 1, 1, dy, 1);
#else
int i;
double *t = dvector(n);
matvectmult(t, c, y, n);
for (i = 0; i < n; i++)
dy[i] = p[i]-t[i];
free_dvector(t);
#endif
}
/* power and temp should both be alloced using hotspot_vector.
* 'b' is the 'thermal conductance' matrix. i.e, b * temp = power
* => temp = invb * power
*/
void steady_state_temp(double *power, double *temp, int n_units)
{
/* set power numbers for the virtual nodes */
set_internal_power(power, n_units);
/* find temperatures */
matvectmult(temp, invb, power, NL*n_units+EXTRA);
}
