cpnet.cpp

神经网络:用感知规则进行感知。。来自网上的代码

	MaxT = abs(Target[0]);
	for(int i = 0; i < target_num; ++i) {
		if(abs(Target[i]) > MaxT) {
			MaxT = abs(Target[i]);
		}
	}
	if(MaxT > 1) {
		for(i = 0; i < target_num; ++i) {
			Target[i] /= MaxT;
		}
	}
}

// denormalize target vector
void CPnet::DeNormalizeTarget() {
	if(MaxT > 1) {
		for(int i = 0; i < target_num; ++i) {
			Target[i] *= MaxT;
		}
	}
}

// compute weighted sum for the current neuron
float CPnet::ComputeWeightedSum( float *Input ) {
	float sum = 0.0f;
	for(int i = 0; i < input_num; ++i) {
		sum += Input[i]*Weight[i];
	}
	return sum;
}

// function for training process
void CPnet::Train() {
    float net;
	int first_index = 0, last_index = input_num;
	bool out;
	for(int i = 0; i < neuron_num; ++i) {
		for(int j = first_index, k = 0; j < last_index; ++j, ++k) {
			input[k] = Input[j];
			if(eAnimType != DEFAULT) {
				cout << Input[j];
				if (j < last_index - 1) {
					cout << ", ";
				}
			}
		}
		net = ComputeWeightedSum(input) + (-1)*threshold;
		if (net>0)
			out = 1;
		else if (net <= 0)
			out = 0;

		Output[i] = out;

		if(eAnimType != DEFAULT) {
			cout << " -> " << out << endl;
			if(eAnimType == ANIM_T3) {
				WAIT(0.1*SECOND);
			}
		}

		float d = Target[i];
		j = first_index;
		for(k = 0; j < last_index; ++j, ++k) {
			delta[k] = LEARNING_RATE*(d-out)*Input[j];
			Weight[k] += delta[k];
		}
		threshold -= (d-out);

		first_index = j;
		last_index += input_num;
	}
	if(bNeuralNetLoaded) {
		bNewModifications = true;
	}
}
	
// function for testing results after training	
void CPnet::Run() {
    float net;
	int first_index = 0, last_index = input_num;
	bool out;
	for(int i = 0; i < neuron_num; ++i) {
		WAIT(0.6*SECOND);
		for(int j = first_index, k = 0; j < last_index; ++j, ++k) {
			input[k] = Input[j];
			cout << Input[j];
			if (j < last_index - 1) {
				cout << ", ";
			}
		}
		net = ComputeWeightedSum(input) + (-1)*threshold;
		if (net>0) {
			out = 1;
		}
		else if (net <= 0) {
			out = 0;
		}

		cout << " -> " << out << endl;

		first_index = j;
		last_index += input_num;
	}
}

// Training Neural Net
void CPnet::TrainNetwork(void) {
	cout << "\nTraining net..." << endl;
	for(int i=0; i<CPN_ITER; ++i) {
		Train();
		if(eAnimType == ANIM_T1 || eAnimType == ANIM_T3) {
			cout << "\nnumber of iterations = " << i + 1 << endl << endl ;
			WAIT(0.3 * SECOND);
		}
		else if(eAnimType == ANIM_T2) {
			cout << "\nnumber of iterations = " << i + 1 << endl << endl;
			WAIT(0.3 * SECOND);
			if (i < CPN_ITER - 1) {
				CLEAR_SCREEN();
			}
		}
		if(eAnimType != DEFAULT && i < CPN_ITER - 1) {
			cout << "\nTraining net..." << endl;
		}
	}
	bNeuralNetTrained = true;
	WAIT(1*SECOND);
	cout << "\n\nTraining completed,";
	ComputeAverageError();
	if (fAverageError <= MIN_ACCURACY) {
		cout << "the learning process was successful!" << endl;
		WAIT(0.6*SECOND);
		cout << "\nNext step: Testing\n\n" << endl;
	} else {
		cout << "learning unsuccessful." << endl;
	}
	UpdateScreen();
}

// computes average error between
// target vector and ouput vector
void CPnet::ComputeAverageError() {
	float sum = 0.0f;
	for(int i = 0; i < target_num; ++i) {
		sum += abs(Target[i] - Output[i]);
	}
	fAverageError = sum/target_num;
}

// Tests the current Neural Net with inputs
void CPnet::TestNetwork(void) {
	cout << "\nTesting \"" << szNeuralNetName << "\" function..." << endl;
	WAIT(0.5*SECOND);
	cout << "\nTest results" << endl;
	Run();
	WAIT(1*SECOND);
	cout << "\nTest completed!" << endl;
	UpdateScreen();
}

// Test the Neural with the selected patterns
void CPnet::SelectiveTest( int pattern_num ) {
	float net;
	int first_index = 0, last_index = input_num;
	bool out;
	int nNumOfInputs = input_num * pattern_num;
	float *Input = new float[nNumOfInputs];
	for(int i = 0; i < nNumOfInputs; ++i) {
		cout << "input[" << i << "] = ";
		cin >> Input[i];
		if ( input_num > 1 && !((i + 1) % input_num)) {
			cout << endl;
		}
		WAIT(0.5*SECOND);
	}

	CLEAR_SCREEN();
	WAIT(0.5*SECOND);
	cout << "\nTesting \"" << szNeuralNetName << "\" function..." << endl;
	WAIT(0.5*SECOND);

	for(i = 0; i < pattern_num; ++i) {
		for(int j = first_index, k = 0; j < last_index; ++j, ++k) {
			input[k] = Input[j];
			cout << Input[j];
			if (j < last_index - 1) {
				cout << ", ";
			}
		}
		net = ComputeWeightedSum(input) + (-1)*threshold;
		if (net>0)
			out = 1;
		else if (net <= 0)
			out = 0;

		cout << " -> " << out << endl;
		WAIT(0.5*SECOND);
		first_index = j;
		last_index += input_num;
	}
	cout << "\nTest completed!" << endl;
	delete Input;
}

void CPnet::UpdateScreen() {
	cout << "Press any key to continue...";
	getch();
	CLEAR_SCREEN();
}

// checks to see if a file or directory exist
// in the current hard drive
bool CPnet::fExist( char* filepath ) {
    WIN32_FIND_DATA file;
    HANDLE hFile;
    if (( hFile = FindFirstFile( filepath, &file ))  
         == INVALID_HANDLE_VALUE ) {
          return false;
    }
    return true;
}

// saves current neural net data before proceding to a new step
void CPnet::SaveCurrentData() {
	if(!bNeuralNetLoaded || (bNeuralNetLoaded && bNewModifications)) {
		if(bNeuralNetCreated && !bNeuralNetSaved) {
			cout << "\nBefore continuing,do you want to save the current Neural Net data?\n"
				<< "Yes(y) No(n): ";
			char response;
			cin >> response;
			response = tolower(response);
			if(response == 'y') {
				SaveNet();
				cout << "The Neural Net was saved successfuly!" << endl;
				UpdateScreen();
			}
		}
	}
}

// Save Neural Net variables to a file
void CPnet::SaveNet(void) {
	FILE *fw = fopen(szNeuralNetName,"w");
	if(!fw) {
		perror(szNeuralNetName);
	}
	// saving input number
	fprintf(fw, "%d\n", input_num);
	// saving neuron number
	fprintf(fw, "%d\n", neuron_num); 
	// saving max input value
	fprintf(fw, "%f\n", Max); 
	// saving max target value
	fprintf(fw, "%f\n", MaxT); 
	// saving the inputs
	total_input_num = input_num * neuron_num;
	for(int i = 0; i < total_input_num; ++i) {
		fprintf(fw, "%f ", Input[i]);
		if (i > 0 && i < total_input_num - 1 && !((i + 1) % 8)) {
			putc('\n', fw);
		}
	}
	// saving the threshold
	fprintf( fw, "\n%f\n", threshold );
	// saving the targets
	for(i = 0; i < target_num; ++i) {
		fprintf(fw, "%f ", Target[i]);
	}
	putc('\n', fw);
	// saving the weights
	for(i = 0; i < input_num; ++i) {
		fprintf(fw, "%f ", Weight[i]);
		if (i > 0 && i < input_num - 1 && !((i + 1) % 8)) {
			putc('\n', fw);
		}
	}
	fflush(fw);
	fclose(fw);

	bNeuralNetSaved = true;
}

// Load Neural Net variables from a file
void CPnet::LoadNet(void) {
	FILE *fw = fopen(szNeuralNetName,"r");
	if(!fw) {
		perror(szNeuralNetName);
	}
	// loading input number
	fscanf(fw, "%d", &input_num);
	// loading neuron number
	fscanf(fw, "%d", &neuron_num);
	// loading max input value
	fscanf(fw, "%f", &Max);
	// loading max target value
	fscanf(fw, "%f", &MaxT);
	// loading the Inputs
	if(Input != NULL) {
		delete Input;
	}
	if(input != NULL) {
		delete input;
	}
	if(Output != NULL) {
		delete Output;
	}
	if(Target != NULL) {
		delete Target;
	}
	if(delta != NULL) {
		delete delta;
	}
	bNeuralNetTrained = false;
	total_input_num = input_num * neuron_num;
	Input = new float[total_input_num];
	if(!Input) {
		std::cerr << "Error while allocating memory for inputs.\n";
	}
	input = new float[input_num];
	if(!input) {
		std::cerr << "Error while allocating memory for temporary inputs variable.\n";
	}
	Target = new float[neuron_num];
	if(!Target) {
		std::cerr << "Error while allocating memory for targets.\n";
	}
	Output = new float[neuron_num];
	if(!Output) {
		std::cerr << "Error while allocating memory for outputs.\n";
	}
	delta = new float[neuron_num];
	if(!delta) {
		std::cerr << "Error while allocating memory for delta.\n";
	}
	// loading the inputs
	for(int i = 0; i < total_input_num; ++i) {
		fscanf(fw, "%f", &Input[i]);
	}
	// loading the threshold
	fscanf(fw, "%f", &threshold);
	// loading the targets
	for(i = 0; i < neuron_num; ++i) {
		fscanf(fw, "%f ", &Target[i]);
	}
	// loading the weights
	if(Weight != NULL) {
		delete Weight;
	}
	Weight = new float[input_num];
	if(!Weight) {
		std::cerr << "Error while allocating memory for weights.\n";
	}
	for(i = 0; i < input_num; ++i) {
		fscanf(fw, "%f", &Weight[i]);
	}
	target_num = neuron_num;
	bNeuralNetCreated = true;
	bNeuralNetLoaded = true;
	bNewModifications = false;
	if(Max > 0 && MaxT > 0) {
		bNeuralNetTrained = true;
	}
	fclose(fw);
}