Today I am given an assignment to find the zeroes of a function using Newton-Raphson method. Till now, the input I gave to a program was data. But now the function (whose zeroes are to be calculated) is also an input.
Is there a way where I can compile and build a function into a file and during execution of my program open the file and run the machine-language code in it and get the return value?
I have a c file which can be compiled in Linux via GCC , but when I compile it in NetBeans via Cygwin or MinGW , it doesn't work and keeps throwing a segmentation fault.
View 14 Replies View RelatedMy socket.cpp program got error. it showed "socket.h: no such file or directory". I had put my header file (socket.h) in the same place with my source file.
View 1 Replies View RelatedI am working on a script compiler that must output compiled script into binary file. Compiling etc is not a problem. The problem is detecting some specific cases. Nothing seems to work. If it works, then it breaks as soon as i modify the script.
Here is example "script1":
Code:
1VAR1 c1 = 44
2VAR2 c2 = 66
3beginscript
4if(c1=44)
5do_nothing
[Code] ....
Second example "script2", when there can be also some command between ENDIF and ENDIF. In this case: do_nothing command.
Code:
1VAR1 c1 = 44
2VAR2 c2 = 66
3beginscript
4if(c1=44)
5do_nothing
[Code] ....
The INDEXES before each line are not in actual script. They are just to point YOU to specific lines. Although the INDEXes are in compiled script!! This is very important. As you see there can be simple IF_ENDIF and nested (more complex) IF_ENDIF.
i.e IF_ENDIF inside another IF_ENDIF.
There are also IF_ELSE_ENDIF and some other ones, but im trying to make simple IF_ENDIF work first.
ENDIF is "SPECIAL" command, the IF, DO_NOTHING are "usual" commands.
"Usual" commands must always jump over(!) the ENDIF. ALWAYS!!
They must "ignore" them!
One strong RULE is like this for usual commands: always jump over any ENDIF, not matter what. If there is one, two or more ENDIF's in a row, then just jump over them to the closest NEXT usual block command. If there is some "usual" block command between multiple ENDIFs, then jump to this command and this command must therefore check whats next command right after it. And do the same: check if next command is ENDIF, if yes, jump over it, until "usual" block command is found.
This is the place im stuck. When i some time ago thinked about some ideas, i saw some patterns. One of them was that: Seems like if its nested IF_ENDIF, then every usual block command jumps out of it, i.e. right after the final ENDIF of this current nested IF_ENDIF.
But as soon as i added do_nothing between the two ENDIFs the so called "pattern" broke. In script2 above you see index 11 is do_nothing. Ok its in nested IF_ENDIF it should jump out to command index 17. But no, because there is do_nothing between index 13 and 16. If we jump out at index 11, the command 14 would never execute. This is a BIG NO. One idea i was thinking and trying was to use STL::FIND, STL::FIND_IF to find next "usual" command after specific index. But my code seems to crash sometimes and not work always.
Code:
bool NextNonENDIF(int i) {
return (i!=98);
}
int findNextBlockCmd(vector<int>&vec, int curidx)
[Code] ....
Here i pass him the vector that contains all the command TYPES in current script. Each command has its own TYPE or better called unique ID in which way compiler knows what is what. So in this case im trying to find a command thats NOT "ENDIF", in other words im trying to find next usual command after specific type of command. Lets just say the TYPE or unique ID of do_nothing is 555, im trying to find it.
How i should continue with this? What to use maybe stl::stack, some custom command indexing, some sort of labelling for usual commands in nested IF_ENDIFs or what?
In general, look script2, and i ask: There is index 11, this guy should look if there is any usual block command left for him before the final ENDIF at index 16. If there is, jump to it. If there is none, jump out of this nested IF_ENDIF to index 17.
Question: how to do it? What algorithms to use? I can use STL, BOOST, whatever. And i can use C++11.
I am using visual studio 2012 on windows 7. but, when I have compiled my programs and run them on an older pc to test out its functions, I receive an error saying that the program is not a "valid win32 application." I have even tested this with a very simple hello world console application, but the problem still remains. Where is the error coming from? is the application corrupted during transport? (upload to internet) or are programs compiled on win 7 incompatible with win xp
View 6 Replies View RelatedI have a weird problem, my computer restarts imidiately after program writen in dev-cpp is compiled AND run. When I run any program, it lasts about 1 second, then program closes, and computer reboots. It doesn't matter whether program is writen now or earlier, my dev-cpp version is 4.9.9.2. Source code can be as simple as this:
#include <iostream>
#include <conio.h>
using namespace std;
int main() {
getch();
return 0;
}
and it restarts anyway...
(C++ question) I need to be able make a compiled code (like a .dll?) which other programmers can use on linux, win,, mac, etc.
The compiled code would simply do calculations and spit out an answer in memory.
I need it to have certain functions that they can easily call and understand (without actually seeing the source).
I am looking at reducing the size of a compiled executable for easier distribution.
What factors affect the size of an output executable?
Would literally having defined and implemented less functions, would make the exec. smaller? Meaning that instead of have a DLL ( yes im on windows ), I would download the source code of a library and comment out the functions ( and code ) that I am not using -- Would this process decrease the size of my exec.?
I have a C++ code that reads the database password from the registry and decrypts it using CryptUnprotectData. We have to deploy this application on a Windows 7 machine.
When I compile my code on Windows XP and run it on the test Windows 7 machine, it works absolutely fine. When I compile the same code on my laptop having Windows 7 and run it on the test Windows 7 machine, CryptUnprotectData fails with GetLastError() return '87'. If I run this application on my own laptop with Windows 7 on it, it again works fine probably because my laptop has a lot of things installed including Visual Studio and all the service packs etc.
I believe I have missed out installing some dependency on the test Windows 7 machine but I am unable to figure out what is that. What is it that's making the Windows XP compiled code running fine on the test machine and not the code that's compiled on Windows 7.
Here is the call to CryptUnprotectData in the code:
if (CryptUnprotectData(
&cipherText,
NULL,
NULL, // Optional entropy
NULL, // Reserved
NULL, // Optional PromptStruct
CRYPTPROTECT_UI_FORBIDDEN,
&plainText))
[code]....
I would like to have 2 functions. (FYI, I haven't even tested these because I don't have a compiler on this PC, so don't know what they'll do. I'm also new to C++, self-teaching.)
My question is, I'm sure that oFile should be type object (of some sort), not int, but I'm not sure how to reference it correctly so that it passes from FileOpen to main to FileClose.
Code:
#include <iostream> //I/O
using namespace std;
#include <fstream> //files
using namespace ios;
int FileOpen(string fileName) {
ifstream oFile (fileName); //attempt to open file
[Code] ....
I have written a C++ program I have multiple of CSV file used as input, which I open one at a time and close it after extracting data to a output file which is the only file.
I run getline(inFile,line);
outFile << line << endl;
I run this code, and only part of it is goes to the output file I got, also have spacing randomly to specific file and inconsistent
But when I slower the code, like system("Pause") in the loop, I can get extract what I want perfectly....
Is my program running to fast, why getline would be skipping part of what things I want?
I have a function in one src file called from code in a different src file.
In ig_cfunc.cpp
Code:
#include "ig_tools.h"
int x2_count = 0.0;
float rel_branch_degree_tmp = 0.0;
string type;
vector<int> is_disp_type;
[Code] ....
I am getting a linker error,
Code:
ig_cfunc.cpp:1609: error: `calc_rel_branch_degree' undeclared (first use this function)
I have deleted all of the objects and recompiled to make sure that everything is in sync. I can't see what the issue is here and I'm not sure what to do next. This code actually worked until I changed the name of the function, so the types are all correct and such. This is the format I use for all external functions ....
How do I call a class method which is defined in a .hxx file separately to a .cpp file? Is it any different from how we normally do it (using the scope resolution operator after the class name and then the method name with parameters) ?
View 1 Replies View RelatedIn my MFC, CMyPorpertyPageDlg is derived from CPropertyPage. How to access its member function from a nonmember function in the same CPP file?.
void Non_Member_Get_PorpertyPage()
{
CMyPorpertyPageDlg* pPageDlg = ....
}
void foo(FILE *f1, FILE **f2) {
fputs("...", f1);
fputs("...", *f2);
} int main(void) {
FILE *fp1 = fopen(...),
*fp2 = fopen(...);
if(fp1 && fp2) {
foo(fp1, &fp2);
...
}
...
}
Forever, I've passed FILE objects into functions like the first parameter; I've never had an issue reading or writing files using that form - no file errors, no compiler warnings, etc. Recently, I saw the second parameter form, and wondered why that was?
I still don't quite get this part of pointers. What's the second parameter form doing differently than the first when the first version *appears* to work as intended??
I have an assignment where I have to alter a ppm image and send it to a function in another file to print the new altered version.
#include "transform.h"
int main (int argc, char *argv[]) {
// declarations here
FILE *inFile;
// open input file
inFile = fopen("tiger.ppm", "r")
[Code] ....
I am trying to include a function from a header file named headerfunt.h . The code of my header file is
Code:
#ifndef HEADERFUNCT_H_INCLUDED
#define HEADERFUNCT_H_INCLUDED
#include <iostream>
[Code]....
But, while compiling it says abs was not declared... I have included the file.
I want to do a basic thing but for some strange reason there is something not working.
I need to write to a file but I'm handling all the code in a callback function, which in turn is declared in a class. Here is the architecture of my code:
Code:
int main (int argc, char **argv) {
ImageConverter Aclass;
while(1); //infinite loop
return 0;
[Code] ....
But this doesn't work, the file gets created but it allways overwrites itself which is not what I need to do.
What I am doing wrong? Is it because i am constantly declaring outfile?
#include <iostream>
#include <cwchar>
#include <string>
#include <Windows.h>
using namespace std;
#include <shellapi.h>
#pragma comment(lib,"shell32.lib")
static HWND hBut;
#define ShellExecute;
[Code] ....
My function is the issue. I'm not sure how to write a correct function to search your computer for file 'a'.
how do you open a file inside of a void function
this is the code i have
#include <iostream>
#include <fstream>
#include <sstream>
[Code]....
ok so I have three numbers in a file that I called in a function and I want to use all three numbers from that file in another function how can I??
View 9 Replies View RelatedI am work on building a simple parse tree and the layout of my code look like this:
Headers
pt_node.hiterator.hparsetree.h
Source files
node.cppparsetree.cppmain.cpp
I am still relatively new to C++ , and have been advised to include function definition for the member function of both pt_node class and iterator class in the node.cpp file
I particular I have declare the following iterator.h:
inline bool operator ==(const tree_iterator& rhs);
which is defined in node.cpp as:
inline bool tree_iterator::operator==(const tree_iterator& rhs) {
return (node ==rhs.node);
}
However on building I receive the following error:
undefined reference to `dnkmat001::tree_iterator::operator==(dnkmat001::tree_iterator const&)'
Why is this occurring and what measure can I take to fix my code
I have to convert a binary value from an input file (the name of which is given by the user) and then convert the binary to decimal value and print that in an output file.
Right now it is compiling just fine with no error messages, but when I run the program, it doesn't end or print to the output file.
Here is my code at the moment:
#include <cstdlib>
#include <iostream>
#include <iomanip>
#include <fstream>
[Code].....
If there are two projects A and B. A is created as .dll, while B is created as static library.
project A has a class "classA"
classA: public classB {
public:
testA();
};
project B has a class "classB"
classB {
public:
testB();
} ;
I want to make a symbol of classB::testB() in A.exp (like ?testB@classB@@QAEXXZ), can I do it by using __declspec(dllexport)?
Also if I make classB as a template class, can the symbol of classB::testB() be generated automatically in A.exp when building project A?
I'm writing a small function that gets as parameter a file's path and a folder's path, and copies the given file to that folder.
Code:
int copy_file(const char* source, const char* folder) {
char copy[PATH_MAX];
strcpy(copy, folder);
strcat(copy, "/");
strcat(copy, source);
[Code] ....
Basically, this function purpose is to make a backup of source in folder every X minutes (depending on user's input).
The problem is the second call to open():
This call attempts to open the file for writing, and creates it if it is not already exist.
It also truncates it before writing to it - and that's my concern:
Let's say this is the second time this function runs, so copy is already exist. open() will then truncate it, and then one of the system calls in the while loop fails.
In this situation, I might be left with no backup file.
The problem also arises for when source is a read-only file:
If source is a read-only file, and copy is not already exist (meaning - it's the first backup attempt), then everything's fine, but, if source is a read-only file and copy is already exist, then I have to first remove copy altogather, and make a fresh copy of source.
Making a backup with new name for copy every time copy_file() runs, will solve this problem, and how can this be accomplished?
I should say that I'd really prefer that copy and source will have the same names when copy_file() returns...