This is a piece of code for my project. I have such a program and I have a problem with filling an array in the graph. I think that the problem with new, but I don't understand what exactly. There is an error:
the expression must have an object pointer type and I don't know what to do with it. I'm a beginner in C++
I tried to use a . instead of -> but it was wrong
#include <iostream>
#include <string>
#include <cstring>
#include <cstdlib>
#include <ctime>
using namespace std;
const int k = 3;
const int N = 1000;
struct Graph
{
struct Node *head[N];
};
struct Node
{
int dest;
int age;
string name;
string surname;
struct Node *next;
};
typedef Node* nodePtr;
struct Graph* createGraph(int );
void printGraph(struct Graph*);
void searchFor( int prefer[2*k][k], struct Graph* graph);
void createArray(struct Graph*, int arr[2*k][k]);
bool Preferences(int pref[2 * k][k], int w, int m, int m1);
int main()
{
int n;
int array[2 * k][k];
cout << "How many persons u want to have?" << endl;
cin >> n;
struct Graph *graph = createGraph(n);
printGraph(graph);
createArray(graph,array);
searchFor(array, graph);
return 0;
}
struct Graph* createGraph( int n)
{
int i,temp,j;
int b = n / 2;
int k, x = 0;
struct Graph *graph = new Graph;
for (i = 0; i < N; i++)
{
graph->head[i] = NULL;
}
srand(time(NULL));
for (i = 0; i < n; i++)
{
struct Node *newNode = new Node;
for ( k = 0; k < b; k++)
{
int m = b;
newNode->dest[k] = m;// here
b++;
}
for (int l = b; l < n; l++)
{
newNode->dest[l] = x; //here
x++;
}
for (int z = 0; z < b; z++)
{
if (z < b)
{
j = rand() % n + b;
temp = newNode->dest[z];
newNode->dest[z] = temp;
}
else
{
j = rand() % b + 0;
}
}
newNode->age = rand() % 90 + 1;
newNode->name = 'A' +(rand()%26);
newNode->surname = newNode->name = 'A' + (rand() % 26);
newNode->next = graph->head[i];
graph->head[i] = newNode;
}
return graph;
}
This statement:
newNode->dest[k] = m;
is illegal because dest was declared as an int. You can't use operator[] on an integer.
You have two main options to fix this:
Write newNode->dest = m; if you want to change the value of newNode->dest to m, or
Change dest to an integer array if you want multiple values to be held in it.
So I have my program here:
#include <iostream>
#include <string>
#include <pthread.h>
#include <unistd.h>
#include <math.h>
#include <stdlib.h>
using namespace std;
int const size = 3;
struct Arguments{
int array[];
float result1[];
float result2[];
};
//void calc(int arr[], float rarr1[], float rarr2[], int size);
void* calc(void *param);
int main(int argc, char *argv[]){
time_t t;
srand((unsigned) time(&t));
int arr[size][size] = {};
float rarr1[size][size-1] = {};
float rarr2[size][size-1] = {};
for(int x = 0; x < size; x++){
for(int y = 0; y < size; y++){
int number = rand()%10;
arr[x][y] = number;
}
}
for(int x = 0; x < size; x++){
for(int y = 0; y < size; y++){
cout << arr[x][y] << " ";
}
cout << endl;
}
cout << endl;
/////////////////////////////////////////
pthread_t child;
struct Arguments input;
for(int i = 0; i < size; i++){
input.array[i] = arr[0][i];
}
pthread_create(&child, NULL, calc, (void*)&input);
pthread_join(child, NULL);
//calc(&input);
for(int i = 0; i < size-1; i++){
rarr1[0][i] = input.result1[i];
cout << "Test: " << rarr1[0][i] << endl;
}
//////////////////////////////////
return 0;
}
//void calc(int arr[], float rarr1[], float rarr2[], int size){
void* calc(void *param){
struct Arguments *input = (struct Arguments*)param;
int arr1[] = {};
float rarr1[] = {};
float rarr2[] = {};
for(int i = 0; i < size; i++){
arr1[i] = input->array[i];
}
for(int i = 0; i < size; i++){
int a = arr1[i];
int b = arr1[i+1];
int difference = a-b;
if(difference < 0){
difference = difference * -1;
}
float euc = 1 + pow(difference, 2);
euc = sqrt(euc);
rarr1[i] = euc;
}
for(int i = 0; i <size-1; i++){
input->result1[i] = rarr1[i];
}
for(int i = 0; i <size-1; i++){
int a = arr1[i];
int b = arr1[i+1];
int difference = a-b;
if(difference < 0){
difference = difference * -1;
}
float apar = (difference/rarr1[i]);
float result = asin(apar);
result = result*(180/3.14);
rarr2[i] = result;
}
return NULL;
}
The important part that causes the trouble is between ////// lines but I left the rest of the code for the context, since it might be useful.
So I have the function calc(param); that does the important calculation in the program.
It is working just fine as long as I call it myself (by actually including the function call in the code) and the test loop right after it gives the correct results.
However, when I try to use pthread_create(); to create a new thread that will take care of executing that function, the test loop spits out nonsense and some random huge numbers different each time.
It's kinda weird because the code compiles either way, and literally the only thing that I change is these 2 lines.
What am I doing wrong and why the function spits out garbage when started by the Pthread? Is there a way to fix it?
Ok so if anyone's having a similar problem:
Declare the size of arrays no matter what. It turns out that my program didn't work properly because I initialized my result arrays as float result1[]; instead of float result1[size];
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Closed 8 years ago.
Improve this question
So far, I wrote my code in C (performance is of utmost importance). However, I would like to start writing my algorithms in a generic way. So, I decided to try out C++. I took a simple code in C and translated it into C++ with templates. To my disappointment, the C++ code runs 2.5 times slower. (the C code is compiled with gcc -O3; the C++ code is compiled with g++ -O3)
Am I doing something wrong in C++? Why is there such a performance hit?
Here is the C code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
static int df_output = 0;
int nCalls = 0;
typedef struct {
int *pancakes;
int n;
} STATE;
STATE **solution;
void shuffle(STATE *s) {
int i;
for (i = 0; i < s->n; i++) {
int i1 = rand() % s->n;
int i2 = rand() % s->n;
int temp = s->pancakes[i1];
s->pancakes[i1] = s->pancakes[i2];
s->pancakes[i2] = temp;
}
}
STATE *copyState(STATE *s) {
STATE *res = malloc(sizeof(STATE));
res->n = s->n;
res->pancakes = (int *)malloc(res->n * sizeof(int));
memcpy(res->pancakes, s->pancakes, res->n * sizeof(int));
return res;
}
// reverse n pancakes
void makeMove(STATE *s, int n) {
int i;
for (i = 0; i < n/2; i++) {
int temp = s->pancakes[i];
s->pancakes[i] = s->pancakes[n - 1 - i];
s->pancakes[n - 1 - i]=temp;
}
}
void printState(STATE *s) {
int i;
printf("[");
for (i = 0; i < s->n; i++) {
printf("%d", s->pancakes[i]);
if (i < s->n - 1)
printf(", ");
}
printf("]");
}
int heuristic(STATE *s) {
int i, res = 0;
nCalls++;
for (i = 1; i < s->n; i++)
if (abs(s->pancakes[i]-s->pancakes[i-1])>1)
res++;
if (s->pancakes[0] != 0) res++;
return res;
}
void tabs(int g) {
int i;
for (i = 0; i < g; i++) printf("\t");
}
int df(STATE *s, int g, int left) {
int h = heuristic(s), i;
if (g == 0) printf("Thereshold: %d\n", left);
if (df_output) {
tabs(g);
printf("g=%d,left=%d ", g, left); printState(s); printf("\n");}
if (h == 0) {
assert(left == 0);
solution = (STATE **)malloc((g+1) * sizeof(STATE *));
solution[g] = copyState(s);
return 1;
}
if (left == 0)
return 0;
for (i = 2; i <= s->n; i++) {
makeMove(s, i);
if (df(s, g+1, left-1)) {
makeMove(s, i);
solution[g] = copyState(s);
return 1;
}
makeMove(s, i);
}
return 0;
}
void ida(STATE *s) {
int threshold = 0, i;
while (!df(s, 0, threshold)) threshold++;
for (i = 0; i <= threshold; i++) {
printf("%d. ", i);
printState(solution[i]);
printf("\n");
//if (i < threshold - 1) printf("->");
}
}
int main(int argc, char **argv) {
STATE *s = (STATE *)malloc(sizeof(STATE));
int i, n;
int myInstance[] = {0,5,4,7,2,6,1,3};
s->n = 8;
s->pancakes = myInstance;
printState(s); printf("\n");
ida(s);
printf("%d calls to heuristic()", nCalls);
return 0;
}
Here is the C++ code:
#include <iostream>
#include "stdlib.h"
#include "string.h"
#include "assert.h"
using namespace std;
static int df_output = 0;
int nCalls = 0;
class PancakeState {
public:
int *pancakes;
int n;
PancakeState *copyState();
void printState();
};
PancakeState *PancakeState::copyState() {
PancakeState *res = new PancakeState();
res->n = this->n;
res->pancakes = (int *)malloc(this->n * sizeof(int));
memcpy(res->pancakes, this->pancakes,
this->n * sizeof(int));
return res;
}
void PancakeState::printState() {
int i;
cout << "[";
for (i = 0; i < this->n; i++) {
cout << this->pancakes[i];
if (i < this->n - 1)
cout << ", ";
}
cout << "]";
}
class PancakeMove {
public:
PancakeMove(int n) {this->n = n;}
int n;
};
class Pancake {
public:
int heuristic (PancakeState &);
int bf(PancakeState &);
PancakeMove *getMove(int);
void makeMove(PancakeState &, PancakeMove &);
void unmakeMove(PancakeState &, PancakeMove &);
};
int Pancake::bf(PancakeState &s) {
return s.n - 1;
}
PancakeMove *Pancake::getMove(int i) {
return new PancakeMove(i + 2);
}
// reverse n pancakes
void Pancake::makeMove(PancakeState &s, PancakeMove &m) {
int i;
int n = m.n;
for (i = 0; i < n/2; i++) {
int temp = s.pancakes[i];
s.pancakes[i] = s.pancakes[n - 1 - i];
s.pancakes[n - 1 - i]=temp;
}
}
void Pancake::unmakeMove(PancakeState &state, PancakeMove &move) {
makeMove(state, move);
}
int Pancake::heuristic(PancakeState &s) {
int i, res = 0;
nCalls++;
for (i = 1; i < s.n; i++)
if (abs(s.pancakes[i]-s.pancakes[i-1])>1)
res++;
if (s.pancakes[0] != 0) res++;
return res;
}
void tabs(int g) {
int i;
for (i = 0; i < g; i++) cout << "\t";
}
template <class Domain, class State, class Move>
class Alg {
public:
State **solution;
int threshold;
bool verbose;
int df(Domain &d, State &s, int g);
void ida(Domain &d, State &s);
};
template <class Domain, class State, class Move>
int Alg<Domain, State, Move>::df(Domain &d, State &s, int g) {
int h = d.heuristic(s), i;
if (g == 0)
cout << "Thereshold:" << this->threshold << "\n";
if (this->verbose) {
tabs(g);
cout << "g=" << g;
s.printState(); cout << "\n";
}
if (h == 0) {
solution = (State **)malloc((g+1) * sizeof(State *));
solution[g] = s.copyState();
return 1;
}
if (g == this->threshold)
return 0;
for (i = 0; i < d.bf(s); i++) {
Move *move = d.getMove(i);
d.makeMove(s, *move);
if (this->df(d, s, g+1)) {
d.unmakeMove(s, *move);
solution[g] = s.copyState();
delete move;
return 1;
}
d.unmakeMove(s, *move);
delete move;
}
return 0;
}
template <class Domain, class State, class Move>
void Alg<Domain, State, Move>::ida(Domain &d, State &s) {
int i;
this->threshold = 0;
while (!this->df(d, s, 0)) threshold++;
for (i = 0; i <= threshold; i++) {
cout << i << ".";
this->solution[i]->printState();
cout << "\n";
//if (i < threshold - 1) printf("->");
}
}
int main(int argc, char **argv) {
Pancake *d = new Pancake();
PancakeState *s = new PancakeState();
int myInstance[] = {0,5,4,7,2,6,1,3};
s->pancakes = myInstance;
s->n = 8;
s->printState(); cout << "\n";
Alg<Pancake, PancakeState, PancakeMove> *alg = new Alg<Pancake, PancakeState, PancakeMove>();
//alg->verbose = true;
alg->ida(*d, *s);
cout << nCalls < "calls to heuristic()";
delete alg;
return 0;
}
You have a lot of malloc() and operator new calls in there. Stop doing that, and performance will improve. And don't use malloc() in C++, use operator new always.
For example, PancakeMove is a small, trivial struct. But you allocate instances of it dynamically, which is slow. Just pass it around by value.
Basically, you are allocating a lot of small things on the heap instead of on the stack. That's pretty "expensive", so will take extra time.
This code (which is modified from your original code) runs within 1ms of the C code:
#include <iostream>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <vector>
using namespace std;
static int df_output = 0;
int nCalls = 0;
class PancakeState {
public:
PancakeState(int n) : n(n), pancakes(n)
{
}
PancakeState(int n, int *v) : n(n), pancakes(n)
{
for(int i = 0; i < n; i++)
pancakes[i] = v[i];
}
PancakeState(): n(0) {}
public:
vector<int> pancakes;
int n;
PancakeState *copyState();
void printState();
};
void PancakeState::printState() {
int i;
cout << "[";
for (i = 0; i < this->n; i++) {
cout << this->pancakes[i];
if (i < this->n - 1)
cout << ", ";
}
cout << "]";
}
class PancakeMove {
public:
PancakeMove(int n) : n(n) {}
int n;
};
class Pancake {
public:
int heuristic (PancakeState &);
int bf(PancakeState&);
PancakeMove getMove(int);
void makeMove(PancakeState &, PancakeMove &);
void unmakeMove(PancakeState &, PancakeMove &);
};
int Pancake::bf(PancakeState& s) {
return s.n - 1;
}
PancakeMove Pancake::getMove(int i) {
return PancakeMove(i + 2);
}
// reverse n pancakes
void Pancake::makeMove(PancakeState &s, PancakeMove &m) {
int i;
int n = m.n;
for (i = 0; i < n/2; i++) {
int temp = s.pancakes[i];
s.pancakes[i] = s.pancakes[n - 1 - i];
s.pancakes[n - 1 - i]=temp;
}
}
void Pancake::unmakeMove(PancakeState &state, PancakeMove &move) {
makeMove(state, move);
}
int Pancake::heuristic(PancakeState &s) {
int i, res = 0;
nCalls++;
for (i = 1; i < s.n; i++)
if (abs(s.pancakes[i]-s.pancakes[i-1])>1)
res++;
if (s.pancakes[0] != 0) res++;
return res;
}
void tabs(int g) {
int i;
for (i = 0; i < g; i++) cout << "\t";
}
template <class Domain, class State, class Move>
class Alg {
public:
vector<State> solution;
int threshold;
bool verbose;
int df(Domain &d, State &s, int g);
void ida(Domain &d, State &s);
};
template <class Domain, class State, class Move>
int Alg<Domain, State, Move>::df(Domain &d, State &s, int g) {
int h = d.heuristic(s), i;
if (g == 0)
cout << "Thereshold:" << threshold << "\n";
if (this->verbose) {
tabs(g);
cout << "g=" << g;
s.printState(); cout << "\n";
}
if (h == 0) {
solution.resize(g+1);
solution[g] = s;
return 1;
}
if (g == this->threshold)
return 0;
for (i = 0; i < d.bf(s); i++) {
Move move = d.getMove(i);
d.makeMove(s, move);
if (this->df(d, s, g+1)) {
d.unmakeMove(s, move);
solution[g] = s;
return 1;
}
d.unmakeMove(s, move);
}
return 0;
}
template <class Domain, class State, class Move>
void Alg<Domain, State, Move>::ida(Domain &d, State &s) {
int i;
this->threshold = 0;
while (!this->df(d, s, 0)) threshold++;
for (i = 0; i <= threshold; i++) {
cout << i << ".";
solution[i].printState();
cout << "\n";
//if (i < threshold - 1) printf("->");
}
}
int main(int argc, char **argv) {
Pancake d = Pancake();
int myInstance[] = {0,5,4,7,2,6,1,3};
PancakeState s(8, myInstance);
s.printState(); cout << "\n";
Alg<Pancake, PancakeState, PancakeMove> *alg = new Alg<Pancake, PancakeState, PancakeMove>();
//alg->verbose = true;
alg->ida(d, s);
cout << nCalls < "calls to heuristic()";
delete alg;
return 0;
}
As an extra benefit of not making so many direct allocations, it also doesn't leak 22 lumps of memory throughout the execution, which is quite a useful feature.
(If you want to see what changed, here's a diff - ignoring whitespace only changes):
--- pcake.orig.cpp 2014-04-13 15:43:24.861417827 +0100
+++ pcake.cpp 2014-04-13 15:42:25.145165372 +0100
## -1,7 +1,9 ##
#include <iostream>
-#include "stdlib.h"
-#include "string.h"
-#include "assert.h"
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <vector>
+
using namespace std;
static int df_output = 0;
## -9,21 +11,22 ##
class PancakeState {
public:
- int *pancakes;
+ PancakeState(int n) : n(n), pancakes(n)
+ {
+ }
+ PancakeState(int n, int *v) : n(n), pancakes(n)
+ {
+ for(int i = 0; i < n; i++)
+ pancakes[i] = v[i];
+ }
+ PancakeState(): n(0) {}
+public:
+ vector<int> pancakes;
int n;
PancakeState *copyState();
void printState();
};
-PancakeState *PancakeState::copyState() {
- PancakeState *res = new PancakeState();
- res->n = this->n;
- res->pancakes = (int *)malloc(this->n * sizeof(int));
- memcpy(res->pancakes, this->pancakes,
- this->n * sizeof(int));
- return res;
-}
-
void PancakeState::printState() {
int i;
cout << "[";
## -37,25 +40,25 ##
class PancakeMove {
public:
- PancakeMove(int n) {this->n = n;}
+ PancakeMove(int n) : n(n) {}
int n;
};
class Pancake {
public:
int heuristic (PancakeState &);
- int bf(PancakeState &);
- PancakeMove *getMove(int);
+ int bf(PancakeState&);
+ PancakeMove getMove(int);
void makeMove(PancakeState &, PancakeMove &);
void unmakeMove(PancakeState &, PancakeMove &);
};
-int Pancake::bf(PancakeState &s) {
+int Pancake::bf(PancakeState& s) {
return s.n - 1;
}
-PancakeMove *Pancake::getMove(int i) {
- return new PancakeMove(i + 2);
+PancakeMove Pancake::getMove(int i) {
+ return PancakeMove(i + 2);
}
// reverse n pancakes
## -91,7 +94,7 ##
template <class Domain, class State, class Move>
class Alg {
public:
- State **solution;
+ vector<State> solution;
int threshold;
bool verbose;
int df(Domain &d, State &s, int g);
## -102,30 +105,28 ##
int Alg<Domain, State, Move>::df(Domain &d, State &s, int g) {
int h = d.heuristic(s), i;
if (g == 0)
- cout << "Thereshold:" << this->threshold << "\n";
+ cout << "Thereshold:" << threshold << "\n";
if (this->verbose) {
tabs(g);
cout << "g=" << g;
s.printState(); cout << "\n";
}
if (h == 0) {
- solution = (State **)malloc((g+1) * sizeof(State *));
- solution[g] = s.copyState();
+ solution.resize(g+1);
+ solution[g] = s;
return 1;
}
if (g == this->threshold)
return 0;
for (i = 0; i < d.bf(s); i++) {
- Move *move = d.getMove(i);
- d.makeMove(s, *move);
+ Move move = d.getMove(i);
+ d.makeMove(s, move);
if (this->df(d, s, g+1)) {
- d.unmakeMove(s, *move);
- solution[g] = s.copyState();
- delete move;
+ d.unmakeMove(s, move);
+ solution[g] = s;
return 1;
}
- d.unmakeMove(s, *move);
- delete move;
+ d.unmakeMove(s, move);
}
return 0;
}
## -138,23 +139,22 ##
for (i = 0; i <= threshold; i++) {
cout << i << ".";
- this->solution[i]->printState();
+ solution[i].printState();
cout << "\n";
//if (i < threshold - 1) printf("->");
}
}
int main(int argc, char **argv) {
- Pancake *d = new Pancake();
- PancakeState *s = new PancakeState();
+ Pancake d = Pancake();
int myInstance[] = {0,5,4,7,2,6,1,3};
- s->pancakes = myInstance;
- s->n = 8;
- s->printState(); cout << "\n";
+ PancakeState s(8, myInstance);
+ s.printState(); cout << "\n";
Alg<Pancake, PancakeState, PancakeMove> *alg = new Alg<Pancake, PancakeState, PancakeMove>();
//alg->verbose = true;
- alg->ida(*d, *s);
+ alg->ida(d, s);
cout << nCalls < "calls to heuristic()";
delete alg;
return 0;
}
+
I have written a binary search like following. When I try to find 10, it's not showing me the result. What am I missing??
// BinarySearch.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
using namespace std;
void BinarySearch(int arr[],int value);
int * insertionshot(int arr[]);
int _tmain(int argc, _TCHAR* argv[])
{
int arr[10] = {1,2,3,10,5,9,6,8,7,4};
int value;
cin >> value ;
static int *ptr;// = new int[10];
ptr = insertionshot(arr);
BinarySearch(ptr,value);
return 0;
}
int * insertionshot(int arr[])
{
int ar[10];
for(int i =0;i < 10; i++)
{
ar[i] = arr[i];
}
int arrlength = sizeof(ar)/sizeof(ar[0]);
for(int a = 1; a <= arrlength -1 ;a++)
{
int b = a;
while(b > 0 && ar[b] < ar[b-1])
{
int temp;
temp = ar[b-1];
ar[b-1] = ar[b];
ar[b] = temp;
b--;
}
}
return ar;
}
void BinarySearch( int a[],int value)
{
int min,max,middle;
min = 0;
int ar[10];
for(int i =0;i < 10; i++)
{
ar[i] = a[i];
}
//printf("size of array = %d",sizeof(arr));
max = (sizeof(ar)/sizeof(ar[0]) -1);
middle = (min+max)/2;
while(min <= max)
{
if(ar[middle] == value)
{
cout << "The value found" << ar[middle];
break;
}
else if(ar[middle] < value)
{
min = middle +1;
}
else if(ar[middle] > value)
{
max = middle-1;
}
middle = (min+max)/2;
}
}
Finally i made it work,I think this code does not have any problem.This could help any one
// BinarySearch.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
using namespace std;
void BinarySearch(int arr[],int value);
int * insertionshot(int arr[],int);
int _tmain(int argc, _TCHAR* argv[])
{
int arr[10] = {1,2,3,10,5,9,6,8,7,4};
int * arr1 = new int[10];
for(int i = 0;i< sizeof(arr)/sizeof(arr[0]);i++)
{
arr1[i] = arr[i];
}
int value;
cin >> value ;
int *ptr = new int[10];
ptr = insertionshot(arr1,10); // address of sorted array will be returned.
BinarySearch(ptr,value);
arr1 = 0;
ptr =0;
delete arr1;
delete ptr;
return 0;
}
int * insertionshot(int arr1[],int n)
{
for(int a = 1; a <= n -1 ;a++)
{
int b = a;
while(b > 0 && arr1[b] < arr1[b-1])
{
int temp;
temp = arr1[b-1];
arr1[b-1] = arr1[b];
arr1[b] = temp;
b--;
}
}
return arr1;
}
void BinarySearch( int a[],int value)
{
int min,max,middle;
min = 0;
int ar[10];
for(int i =0;i < 10; i++)
{
ar[i] = a[i];
}
max = (sizeof(ar)/sizeof(ar[0]) -1);
middle = (min+max)/2;
while(min <= max)
{
if(ar[middle] == value)
{
cout << "The value found" << ar[middle];
break;
}
else if(ar[middle] < value)
{
min = middle +1;
}
else if(ar[middle] > value)
{
max = middle-1;
}
middle = (min+max)/2;
}
}
You're missing the most important part of a binary search: The collection you search in must be sorted.
For binary search, the array should be arranged in ascending or descending order.
I'm writing a genetic algorithm for which I'm creating a "crossover" operator as a class object that is passed the two parent "chromosomes" Because the input and therefore the output chromosomes are variable lengths, my idea was two divide the input chromosomes and place in a sort of storage class variable, then resize the input chromosomes, and then finally refill the input chromosomes. I'm getting a bad_alloc error, however. If someone could spot my error I'd very much appreciate the help.
Thanks! My class code is below. Note that "plan_vector" is a 2d vector of int types.
#include <iostream>
#include <vector>
#include <eo>
class wetland_vector : public std::vector<int> {
public:
wetland_vector() : std::vector<int>(1, 0) {
}
};
std::istream& operator>>(std::istream& is, wetland_vector& q) {
for (unsigned int i = 0, n = 1; i < q.size(); ++i) {
is >> q[i];
}
return is;
}
std::ostream& operator<<(std::ostream& os, const wetland_vector& q) {
os << q[0];
for (unsigned int i = 1, n = 1; i < q.size(); ++i) {
os << " " << q[i];
}
os << " ";
return os;
}
class wetland_vector_Init : public eoInit<wetland_vector> {
public:
void operator()(wetland_vector& q) {
for (unsigned int i = 0, n = q.size(); i < n; ++i) {
q[i] = rng.random(10);
}
}
};
class plan_vector : public eoVector<double, wetland_vector> {
};
int read_plan_vector(plan_vector _plan_vector) {
for (unsigned i = 0; i < _plan_vector.size(); i++) {
//Call function that reads Quad[1]
//Call function that reads Quad[2]
//etc
return 0;
}
return 0;
};
class eoMutate : public eoMonOp<plan_vector> {
int subbasin_id_min;
int subbasin_id_max;
int wetland_id_min;
int wetland_id_max;
bool operator() (plan_vector& _plan_vector) {
//decide which Quad to mutate
int mutate_quad_ID = rng.random(_plan_vector.size());
//decide which Gene in Quad to mutate
int mutate_gene_ID = rng.random(_plan_vector[mutate_quad_ID].size());
//mutation procedure if first slot in the Quad is selected for mutation
if (mutate_quad_ID = 0) {
_plan_vector[mutate_quad_ID][mutate_gene_ID] = rng.random(subbasin_id_max);
}
//mutation procedure if second slot in the Quad is selected for mutation
if (mutate_quad_ID = 1) {
_plan_vector[mutate_quad_ID][mutate_gene_ID] = rng.random(subbasin_id_max);
}
//note: you'll need to add more for additional wetland characteristics
return true;
};
public:
void set_bounds(int, int, int, int);
};
void eoMutate::set_bounds(int a, int b, int c, int d) {
subbasin_id_min = a;
subbasin_id_max = b;
wetland_id_min = c;
wetland_id_max = d;
}
double evaluate(const plan_vector& _plan_vector) {
int count = 0;
for (int i = 0; i < _plan_vector.size(); i++) {
for (int j = 0; j < _plan_vector[i].size(); j++) {
count += _plan_vector[i][j];
}
}
return (count);
}
class eoQuadCross : public eoQuadOp<plan_vector> {
public:
std::string className() const {
return "eoQuadCross";
}
plan_vector a1;
plan_vector a2;
plan_vector b1;
plan_vector b2;
bool operator() (plan_vector& a, plan_vector& b) {
int cross_position_a = rng.random(a.size() - 1);
int cross_position_b = rng.random(b.size() - 1);
for (int i = 0; i < cross_position_a; i++) {
a1.push_back(a[i]);
}
for (int i = cross_position_a; i < a.size(); i++) {
a2.push_back(a[i]);
}
for (int i = 0; i < cross_position_b; i++) {
b1.push_back(b[i]);
}
for (int i = cross_position_b; i < b.size(); i++) {
b2.push_back(b[i]);
}
int size_a = b2.size() + a1.size();
int size_b = a2.size() + b1.size();
a.resize(size_a);
b.resize(size_b);
for (int i = 0; i < b2.size(); i++) {
a.push_back(b2[i]);
}
for (int i = 0; i < a1.size(); i++) {
a.push_back(a1[i]);
}
for (int i = 0; i < a2.size(); i++) {
b.push_back(a2[i]);
}
for (int i = 0; i < b1.size(); i++) {
b.push_back(b1[i]);
};
//Return bool
return true;
}
};
int main() {
unsigned int vec_size_min = 1;
unsigned int vec_size_max = 10;
unsigned int pop_size = 100;
//BEGIN COPY PARAMETRES
const unsigned int MAX_GEN = 100;
const unsigned int MIN_GEN = 5;
const unsigned int STEADY_GEN = 50;
const float P_CROSS = 0.8;
const float P_MUT = 0.5;
const double EPSILON = 0.01;
double SIGMA = 0.3;
const double uniformMutRate = 0.5;
const double detMutRate = 0.5;
const double normalMutRate = 0.5;
//END COPY PARAMETERS
rng.reseed(1);
//Create population
wetland_vector_Init atom_init;
eoInitVariableLength<plan_vector> vec_init(vec_size_min, vec_size_max, atom_init);
eoPop<plan_vector> pop(pop_size, vec_init);
//Create variation operators
eoMutate mutate;
mutate.set_bounds(1, 453, 1, 4);
eoQuadCross crossover;
eoDetTournamentSelect<plan_vector> select(3);
eoSGATransform<plan_vector> transform(crossover, .5, mutate, .2);
//Create fitness function
eoEvalFuncPtr<plan_vector> eval(evaluate);
//Evaluate initial population and cout
apply<plan_vector > (eval, pop);
std::cout << pop << std::endl;
//Set GA for execution and execute
eoGenContinue<plan_vector> GenCount(5);
eoSGA<plan_vector> gga(select, crossover, .5, mutate, .1, eval, GenCount);
gga(pop);
//cout final population and end
std::cout << pop << std::endl;
std::cout << "The End" << std::endl;
}
a1.~vector();
a2.~vector();
b1.~vector();
b2.~vector();
You shall not destruct the vectors manually, otherwise the next time you try to access them (upon next call to the operator ()) you get undefined behavior.
Why do you call vector destructor manually?? You should let C++ call that for you. If you want to clear the vector use clear member function