// [[Rcpp::export]]
List integer_erase_range_2( IntegerVector x, IntegerVector y ){
IntegerVector::iterator it = x.begin()+1 ;
while( it != x.end() ){
it = x.erase(it) ;
}
it = y.begin() + 1 ;
while( it != y.end() ){
it = y.erase(it) ;
}
return List::create( x, y ) ;
}
// [[Rcpp::export]]
List starvingforager_eventNM(
int L, //Lattice dim
int t_term, //Terminal time
double alpha, //Resource growth rate
double K, //Resource carrying capacity
double sigma, //Starvation rate
double rho, //Recovery rate
double lambda, //Growth rate
double mu, //Mortality rate
IntegerVector ind_vec, //Initial vector of states
IntegerVector loc_vec //Initial vector of locations
) {
//Dimension of the lattice
int dim = 2;
//Lattice size
double size = pow(L-2,dim);
//Initial time
double t = 0;
double max;
double min;
//Output Lists
List ind_out(1);
List loc_out(1);
NumericVector t_out(1);
//The initial state
ind_out(0) = ind_vec;
loc_out(0) = loc_vec;
t_out(0) = 0;
//ind_vec: the vector of individual states... 0 = resource, 1=starver, 2=full
//pos_vec: the vector of individual locations
//Initial count of how many resouces, starvers, and full in this timestep??
//Count the number of individual R + S + F
int tot = ind_vec.size();
double R = 0.L;
double S = 0.L;
double F = 0.L;
// double Rp;
// double Sp;
// double Fp;
for (int i=0;i<tot;i++) {
if (ind_vec(i) == 0) {
R = R + 1.L;
}
if (ind_vec(i) == 1) {
S = S + 1.L;
}
if (ind_vec(i) == 2) {
F = F + 1.L;
}
}
//R,S,F are thus densities over the landscape of size 'size'
// R = R/size;
// S = S/size;
// F = F/size;
double R_pr_line;
double S_pr_line;
double F_pr_line;
//Iterate over time
//The loop stops when t > t_term-1... and will record the last value
int tic = 1;
while (t < (t_term-1)) {
//Construct probability lines, which are a function of R, S, F
//Grow <-----> Consumed
R_pr_line = (alpha*(K-R))/((alpha*(K-R)) + (F + S));
//R_pr_line(1) = R_pr_line(0) + ((F + S)/((alpha*(K-R)) + (F + S) + Dr));
//R_pr_line(2) = R_pr_line(1) + (Dr/((alpha*(K-R)) + (F + S) + Dr));
//Recover <-----> Mortality
S_pr_line = (rho*R)/(rho*R + mu);
//S_pr_line(1) = S_pr_line(0) + (mu/(rho*R + mu + Ds));
//S_pr_line(2) = S_pr_line(1) + (Ds/(rho*R + mu + Ds));
//Grow <-----> Starve
F_pr_line = lambda/(lambda+sigma*(K-R));
//F_pr_line(1) = F_pr_line(0) + ((sigma*(K-R))/(lambda+sigma*(K-R)+Df));
//F_pr_line(2) = F_pr_line(1) + (Df/(lambda+sigma*(K-R)+Df));
//Initiate variables
double dt;
//Randomly select an individual (R,S,F) with probability 1/N
//ind thus represents the POSITION of the individual
//Update total number of individuals
tot = ind_vec.size();
max = (double)(tot - 1);
min = 0.L;
int id = min + (rand() % (int)(max - min + 1));
int state;
int location;
double draw_event;
//If ind is a resource...
if (ind_vec(id) == 0) {
state = 0;
location = loc_vec(id);
//Draw a random event
//Grow, become consumed or move?
draw_event = ((double) rand() / (RAND_MAX));
//Grow
if (draw_event < R_pr_line) {
//Append a new resource to the END of the vector
ind_vec.push_back(state);
//Append the resource's location to the END of the vector
loc_vec.push_back(location);
//Update Tally
R = R + 1; //(1.L/size);
}
//Become consumed!!!!
if ((draw_event >= R_pr_line) && (draw_event < 1.L)) {
//Remove the consumed resource from the state vector
ind_vec.erase(id);
//Remove the consumed resource form the location vector
loc_vec.erase(id);
//Update Tally
R = R - 1; //(1.L/size);
}
dt = 1.L/((alpha*(K-R)) + (F + S));
}
//If ind is a starver...
if (ind_vec(id) == 1) {
state = 1;
location = loc_vec(id);
//Draw a random event
//Recover, die, or move??
draw_event = ((double) rand() / (RAND_MAX));
//Recover
if (draw_event < S_pr_line) {
//Update the state from starver to full
ind_vec(id) = 2;
//Update Tally
S = S - 1; //(1.L/size);
F = F + 1; //(1.L/size);
}
//Die
if ((draw_event >= S_pr_line) && (draw_event < 1.L)) {
//Remove the consumed resource from the state vector
ind_vec.erase(id);
//Remove the consumed resource form the location vector
loc_vec.erase(id);
//Update Tally
S = S - 1; //(1.L/size);
}
dt = 1.L/(rho*R + mu);
}
//If ind is Full...
if (ind_vec(id) == 2) {
state = 2;
location = loc_vec(id);
//Draw a random event
//Grow, starve, or move?
draw_event = ((double) rand() / (RAND_MAX));
//Grow
if (draw_event < F_pr_line) {
//Append a new resource to the END of the vector
ind_vec.push_back(state);
//Append the resource's location to the END of the vector
loc_vec.push_back(location);
F = F + 1; //(1.L/size);
}
//Starve
if ((draw_event >= F_pr_line) && (draw_event < 1.L)) {
//Update the state from full to starver
ind_vec(id) = 1;
//Update Tally
F = F - 1; //(1.L/size);
S = S + 1; //(1.L/size);
}
dt = 1.L/(lambda+sigma*(K-R));
}
//Advance time
t = t + dt;
//Rcout << "t = " << dt << std::endl;
//Update output
ind_out.push_back(ind_vec);
loc_out.push_back(loc_vec);
t_out.push_back(t);
tic = tic + 1;
} //end while loop over t
List cout(3);
cout(0) = ind_out;
cout(1) = loc_out;
cout(2) = t_out;
return(cout);
}
// [[Rcpp::export]]
IntegerVector integer_erase2( IntegerVector y ){
y.erase(1,2) ;
return y ;
}
// [[Rcpp::export]]
List integer_erase_range( IntegerVector x, IntegerVector y ){
x.erase(x.begin()+5, x.end()-1 );
y.erase(y.begin()+5, y.end()-1 );
return List::create( x, y ) ;
}
// [[Rcpp::export]]
IntegerVector integer_erase( IntegerVector y ){
y.erase(2) ;
return y ;
}
