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# Need with with some errors

 P: n/a Hi, I am trying to write a program to solve roots using the Newtonian method of roots, and I am recieving several errors which I cannot figure out... if anyone could give me a point in the right direction it wuld be appreciaed. Here is what I have so far: #include #include using namespace std; double getF(double x); //The orgional function double getdF(double x); //The derivative of orgional function //int getRoot(double &rootEst, double tolerance, int maxIterations); const double e = 2.718281828459; double getRoot(double &rootEst, double tolerance, int maxIterations) { int n = 1; while( ( fabs(getF(rootEst)) tolerance ) && ( n <= maxIterations ) ) { rootEst = rootEst - ( getF(rootEst) / getFd(rootEst) ); n++; } return n; } double getF( x ) { return ( pow(x, 2) * pow(e, -1 * x) - 2 ); } double getdF( x ) { return ( 2 * pow(e, -1 * x) * x - pow(x, 2) * pow(e, -x) ); } int main () { double rootEst, //The initial estimate of the root tolerance; //The stopping tolerance int maxIterations, curNumIterations; cout << "Please enter the initial estimate of the root: "; cin >rootEst; cout << "Please enter the tolerance: "; cin >tolerance; cout << "Please enter the maximum allowed iterations: "; cin >maxIterations; cout << endl << "Using the following data" << endl << "Initial guess: " << rootEst << endl << "Tolerance: " << tolerance << ", and" << endl << "Maximum iterations: " << maxIterations << "." << endl; curNumIterations = getRoot(rootEst, tolerance, maxIterations); if(curNumIterations maxIterations) { cout << "After " << maxIterations << " iterations no solution was found!" << endl; } else { cout << "The solution is: " << rootEst << " and it was found in " << curNumIterations << " iterations" << endl; } return 0; } And here are my compile errors: ------ Build started: Project: test, Configuration: Debug Win32 ------ Compiling... assign8.cpp ..\assign8.cpp(18) : error C3861: 'getFd': identifier not found ..\assign8.cpp(27) : error C2065: 'x' : undeclared identifier ..\assign8.cpp(28) : error C2448: 'getF' : function-style initializer appears to be a function definition ..\assign8.cpp(33) : error C2448: 'getdF' : function-style initializer appears to be a function definition Build log was saved at "file://c:\Documents and Settings\Janet Lannon \My Documents\Visual Studio 2005\Projects\test\test\Debug \BuildLog.htm" test - 4 error(s), 0 warning(s) ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== I am a student and new to this, im not looking for someone to give me the complete solution, but hopefully help me realise whats wong with my own. thanks. Mar 21 '07 #1