/**
* Update environmental infectious pressure phi
*
* @param v_new The continuous state vector in the node after the post
* time step
* @param u The compartment state vector in the node.
* @param v The current continuous state vector in the node.
* @param ldata The local data vector for the node.
* @param gdata The global data vector.
* @param node The node.
* @param t Current time.
* @param sd The sub-domain of the node.
* @return error code (<0), or 1 if node needs to update the
* transition rates, or 0 when it doesn't need to update the
* transition rates.
*/
int SISe3_post_time_step(
double *v_new,
const int *u,
const double *v,
const double *ldata,
const double *gdata,
int node,
double t,
int sd)
{
const int day = (int)t % 365;
const double I_n = u[I_1] + u[I_2] + u[I_3];
const double n = I_n + u[S_1] + u[S_2] + u[S_3];
const double phi = v[PHI];
/* Time dependent beta in each of the four intervals of the
* year. Forward Euler step. */
v_new[PHI] = siminf_forward_euler_linear_decay(
phi, day,
ldata[END_T1], ldata[END_T2], ldata[END_T3], ldata[END_T4],
gdata[BETA_T1], gdata[BETA_T2], gdata[BETA_T3], gdata[BETA_T4]);
if (n > 0.0)
v_new[PHI] += gdata[ALPHA] * I_n / n + gdata[EPSILON];
else
v_new[PHI] += gdata[EPSILON];
if (isfinite(v_new[PHI]))
return phi != v_new[PHI]; /* 1 if needs update */
return SIMINF_ERR_V_IS_NOT_FINITE;
}
/**
* Update environmental infectious pressure phi
*
* Decay environmental infectious pressure phi, add contribution from
* infected individuals and proximity coupling.
* @param v_new The continuous state vector in the node after the post
* time step
* @param u The compartment state vector in the node.
* @param v The current continuous state vector in the node.
* @param ldata The local data vector for the node.
* @param gdata The global data vector.
* @param node The node.
* @param t Current time.
* @param sd The sub-domain of the node.
* @return error code (<0), or 1 if node needs to update the
* transition rates, or 0 when it doesn't need to update the
* transition rates.
*/
int SISe_sp_post_time_step(
double *v_new,
const int *u,
const double *v,
const double *ldata,
const double *gdata,
int node,
double t,
int sd)
{
int i, j;
const int day = (int)t % 365;
const double I_n = u[I];
const double n = u[S] + I_n;
const double phi = v[PHI];
const double coupling = gdata[COUPLING];
/* Deterimine the pointer to the continuous state vector in the
* first node. Use this to find phi at neighbours to the current
* node. */
const double *phi_0 = &v[-node];
/* Time dependent decay (beta) of the environmental infectious
* pressure in each of the four intervals of the year. Forward
* Euler step. */
v_new[PHI] = siminf_forward_euler_linear_decay(
phi, day,
ldata[END_T1], ldata[END_T2], ldata[END_T3], ldata[END_T4],
gdata[BETA_T1], gdata[BETA_T2], gdata[BETA_T3], gdata[BETA_T4]);
/* Add contribution from infected individuals */
if (n > 0.0)
v_new[PHI] += gdata[ALPHA] * I_n / n + gdata[EPSILON];
else
v_new[PHI] += gdata[EPSILON];
/* Coupling between neighboring nodes. */
/* i is the offset in local data to the first neighbor. */
/* j is the neighbor node or -1 to stop. */
i = NEIGHBOR;
j = (int)ldata[i];
while (j >= 0) {
v_new[PHI] += (phi_0[j] - phi) * coupling * ldata[i + 1];
/* Move to next neighbor pair (index, value) */
i += 2;
j = (int)ldata[i];
}
if (isfinite(v_new[PHI]))
return phi != v_new[PHI]; /* 1 if needs update */
return SIMINF_ERR_V_IS_NOT_FINITE;
}
