i've defined an strcuct in .h file and i read its variable in a method in .cpp file ,but i'v got error.
.H file:
class myclass{
public:
struct opt_struct
[Code]....
when i declare the struct without static , it doesn't recognize my struct and with static i face linker error:
Error33error LNK1120: 1 unresolved externals
Is it any different when using a class in my code. My previous code i define my struct like this
Code: #include <iostream>
#include <fstream>
#include <string>
struct{
[Code] .....
or do i still define it the same way at the top of my code.
I just wrote a code that reads in a text file called "policies.txt" which looks like this:
Pol1 M N 20 100000 1 .04 99
Pol2 F S 30 100000 1 .05 99
Pol3 M S 72 750000 1 .03 99
Pol4 F N 45 1000000 1 .05 99
This works perfectly fine, but what if I want each element of the table to be separated by commas. For example:
Pol1,M,N,20,100000,1,.04,99
Pol2,F,S,30,100000,1,.05,99
Pol3,M,S,72,750000,1,.03,99
Pol4,F,N,45,1000000,1,.05,99
or better yet, what if I want it to not matter whether the columns are separated by commas or spaces? is there any way to do this? If there is no way to read in both comma-separated and space-separated elements simultaneously then I would prefer just comma, rather than the space separated which my code is able to read now. What modifications would I have to make to my code to make this work? This is my code to reference.
double ratesmn[86] = {
#include "MaleNonSmoker.txt"
- 1
};
double ratesms[86] = {
#include "MaleSmoker.txt"
[Code] ....
If I DEFINE a global variable in two source files which belong to the same project, then there is a linker error "multiply defined symbols". But if I DEFINE a global variable in two source files which belong to the different projects, then it compiles fine. Why?
View 8 Replies View RelatedI am trying to use struct to store variables from a text file and use them in the main program. I have first tried running the program without using struct and declaring the variables within the main program and it runs fine. But after using struct, it gives no compilation error and a segmentation fault as output. Also, if the size of file/variable size is unknown can I declare variables as char string[]??
The code is as below:
Code:
#include<stdio.h>
struct test {
char string1[10000];
[Code].....
Below is the code for reading a struct that was stored in a binary file. Problem is while reading from file I get the name without first character and age is always equal to zero which it should not be.
#include <iostream>
#include <conio.h>
#include <fstream>
struct abc {
char name[100];
int age;
[Code] .....
I have an abstract class called Mbase and from it derived two classes: Sparse and Dense. Now I have an array in which its elements can be either Sparse or Dense. So, I delcared the array to have pointers to Mbase class. For example:
PHP Code:
Mbase** A;
Sparse* A1 = new Sparse;
Dense* A2 = new Dense;
A[1] = dynamic_cast<Mbase*>(A1);
A[2] = dynamic_cast<Mbase*>(A2);
Now, I have operator + defined in Sparse and Dense. but when I do
PHP Code:
A[1]+A[2]
I get that operator + is not defined for Mbase class. So, I tried to define it in the Mbase class
PHP Code:
class Mbase{
public:
void put()=0;
double get()=0;
Mbase operator +(Mbase A);
}
However, the last code does not compile complaining that it cannot declare a class of type abstract in Mbase operator +(Mbase A). I think this is because I am returning Mbase instance.
I am currently stuck on what I should do next in a program I am working on. These are my instructions:
Design, implement, and test a class for storing integer arrays "safely". The array should be able to hold any number of integers up to 100.
In the class header file "SafeArray.h" students must define the class and specify the constructor/destructor functions, the public methods and private variables. In the class implementation file "SafeArray.cpp" students must implement the following operations:
constructor - to initialize the object.
copy constructor - to copy an object.
destructor - to delete the object.
set - allow the user to set a value of the array at a particular location.
get - allow the user to get a value of the array at a particular location.
print - print out the array.
add - add the elements of one array to another.
subtract - subtract the elements of one array from another.
The output of my program is suppose to look like this:
Set q1: 2, 3, 4
Print q1: 2, 3, 4
Set q2: 1, 4, -2
Print q2: 1, 4, -2
Add q2 to q1
Print q1: 3, 7, 2
Get q1 at 1: 7
Here is the code I have so far.
*main.cpp*
#include <iostream>
#include "SafeArray.h"
using namespace std;
int main() {
// Declare a SafeArray object
Safe obj;
[Code] ....
#include "stdafx.h"
#include <iostream>
#include <math.h>
using namespace std;
class Calc {
[Code] ....
when i built it, it showed the following errors:
1>------ Build started: Project: rough, Configuration: Debug Win32 ------
1> rough.cpp
1>e:c programs
ough
ough
ough.cpp(17): error C3872: '0xa0': this character is not allowed in an identifier
1>e:c programs
[Code] ....
Need sorting out the errors!!!
I just read and have known for a while that classes are private (members and inheritance) by default and structs are public. But my question then comes what if.. a struct inheriting from a class or a class inheriting from a struct?
View 3 Replies View RelatedThe question is: Define the class Counter. An instance of this class is used to count things, but the counter should never be less than 0 (non negative number). The member variable should be private. I realize what I'm suppose to be using but can't implement the member functions needed..
int main(){
int value;
cin >> value;
Counter myCounter(value);
for (int i = 1; i <= MAXLOOP; i++) {
myCounter.increment();
[Code] ....
I've been wondering about something for a while:
Is it possible to declare a struct/class, in a cpp file, designed for local use, but with internal linkage?
The usecase is that every once in a while, I want to wrap "startXXX+endXXX" function pairs in a simple RAII struct. I just declare the struct in my cpp and use it once.
However, if I do this, (AFAIK), the compiler will generate an entry in the link table, which means I could potentially have link conflicts if I declare the same struct twice in two different cpp files.
Unless I'm mistaken, since the struct is declared in the same cpp that it is used, I wouldn't need external linkage. Is there a way to avoid it?
I am working on an assignment in which i have to perform th following task
myClass itsObject1,itsObject2;
itsObject2=5000+itsObject1;
I have defined overloaded operator as follows in the header file but in the cpp file of the class it gives error.
friend vli &vli::operator + (int &a,vli &obj);
How to define it in cpp file of my class?
I have a function reads from a file like this
file
foo;bar
foo;bar
foo;bar
function
void EntryList::loadfile(const char filefoo[]){
ifstreamin;
[Code] ....
I am in the middle of rewriting this program for at least the 4 time. and I have modified the file how I (humanly) think I should to this. I have had issues in the past, doing it this way. (still working on the other parts of the program so I cannot be too specific right now, but I know my results were unexpected ) So my question is does the function that I modified look correct for what I am trying to do? Am I off by one? I guess I am struggling with understanding how the original function is working. (step by step systematically.) hence my confusion about my modified function.
I have a file with data in lines separated by commas and im trying to print out specific lines and specific parts of data from that line. I need to isolate lines where the first column of data reads '$CPGAR' and print out specific data columns.When I print out the strings I get random data and my strcmp to isolate lines isnt working? Im very new to this, heres a sample of my program:
while (!feof(gpsH)) {
char word1[10],word2[10],word3[10],word4[10],word5[10],word6[10],word7[10],
word8[10],word9[10],word10[10],word11[10],word12[10],word13[10];
char a[6] ="$CPGAR";
/* read data line */
fgets(gpsS,10,gpsH);
[Code]...
I 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
Suppose I have the following sample header file test.h
Code:
#include "myCommon.h"
class Test {
public:
Test();
vector<vector<vector<double>>> vI3(dim1, vector<vector<double>> (dim2, vector<double> (dim2, 0.0f)));
private:
fillVector();
}
In above test.h dim1 and dim2 are defined in a different header file, i.e. myCommon.h
Code:
const long dim1 = 40;
enum dimVector {
RED,
GREEN,
dim2
};
However, it gives the errors when I compile: variable "dim1" is not a type name and for variable "dim2" it complains about a duplicate parameter name.
The declarations of dim1 and dim2 should stay in myCommon.h. They can also be defined in myCommon.cpp if needed, but can't go into test.h.
I am attempting to read in a file that has 4128 sets of 21 numbers separated by commas and write it into an array. I now know that in order to use fseek, I have to make my array a character array, but I need my function to read in decimals (ex: 0.172635). I'm reading in
0.102598,0.000000,0.000000,0.000000,0.000000,0.307 793,0.000000,0.410391,0.102598,0.000000,0.102598,0 .102598,0.000000,0.000000,0.102598,0.102598,0.8207 83,0.000000,0.000000,0.000000,0.000000
and keep getting numbers like 48 49 50.
Code:
void CSread(char filename[100], char array[22], char array2[22], unsigned int arraysize)
{
char genename[32];
double temp = 0;
FILE *CSfile;
CSfile = fopen(filename, "r");
");
[code].....
I tried to read in a file that contain studentId(8 integer long) and GPA in the same line separated by a comma, but I couldn't. Example:
145453565, 4.0
34344443, 3.9
23454345, 3.4
12345678, 3.4
void studentRecord::loading(string filename) {
ifstream infile;
int studentId;
double GPA;
[Code] ....
Write a program that opens a file and counts the whitespace-separated words in that file.?
My code that i wrote for this example is as follows...
#include <iostream>
using namespace std;
#include <iostream>
#include <string>
#include <fstream>
int main() {
string filename = "Question 1.cpp"; // File name goes in here
[Code] ....
Is this correct or am i missing something?
I have been trying to read a comma separated .txt file into an array and print it to console in C++. The txt file consists of two columns of double type data. For some reason the program runs, but gives blank output in the console. I want to know if I am doing something wrong. So far this is what I have:
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
int main() {
int i=0;
double x[10];
double y[10];
string line;
[Code] .....
Question is : Write a program that opens a file and counts the whitespace-separated words in that file.?
my answer is :
#include <iostream>
using namespace std;
#include <iostream>
#include <string>
#include <fstream>
int main() {
string filename = "Question 1.cpp"; // File name goes in here
[Code] ....
Now I am not sure if im suppose to get a msg saying : The file "Question 1.cpp" has 0 words.
im wondering is the question that im being asked, asking me to input a string of words and then the compiler when it builds and runs the program counts the word spaces.?
Basically, I have made a program which implements the platform specific layers (such as entry function, file loading, timing functions etc.) that gets compiled into a .exe (or platform equivalent).
But I want to make this portable and reusable across other projects, so the entry function for the platform will call the function "AppMain" which is the generic main function that is not reliant on the underlying platform etc. (i.e defined in a .h file that the project module will implement).
Ideally I would want to build the AppMain code into its own library. However, This AppMain code would want access to the Platform functions such as the functions compiled into the .exe.
This has confused me somewhat and has forced me to build both the AppMain module and the Platform Code into the same exe file so they can use each others functions.
Is there any way I can create a header file (with all the function prototypes in) but they do not get implemented in the Platform code but rather they can be 'guaranteed' to be available at runtime?
Here is what I am trying to achieve in a high level view:
win32layer.cpp: (implements all the functions defined in Platform.h)
#include <AppMain.h>
int main(int argc, char** argv) {
//call AppMain
return AppMain(argc, argv);
[Code] ....
in this scenario of course I could not compile the platform functions as the application has not been created and thus appmain cannot call the platform functions because that has not been created etc....
Any way to overcome this?
Well I tried to assign a new char value from a struct to another char variable but I got the "Cannot convert 'int' to 'char'" error when compiling. I've tried several alternations but I still can't get away with this error.
Here's a section of the code:
javascript:tx('code')
for(int i = 0 ; i < 10 ; i++){
pts[i].dist = sqrt((pts[i].x*pts[i].x)+(pts[i].y*pts[i].y));
}
[Code].....
Okay so I'm writing a simple program - so far with just 1 header and 1 .cpp file to go with it. I'm getting strange errors saying that my struct hasn't been recognised even though I declare it in the header. The code involved is --
Code:
#include<stdio.h>
#include<iostream>
#include<sstream>
#include"bots.h"
//#include"prisonersDilemna.h"
//write program to battle multiple bots with a random choice generator
//and after all iterations post who comes out on top.
[Code] ....
||=== Build finished: 6 errors, 0 warnings ===|
How should the syntax be? Why does my program not recognise bot as an object type? Why can I not have a void method?
I've been working on a path-tracer for some time, and all along I've used structs instead of classes for vectors and matrices. Today I changed all of them to classes instead, changing none of the actual function bodies themselves, and the results were miserable to say the least.
Here's a render form before the change: [URL] ....
And here's the same render after: [URL] ....
Why this is happening, considering that none of the actual function-bodies have been changed, except for what little is needed to make the change from class to struct.