Goal:
Read contents from a file and use as the size of a 2d array.
Problem:
C2087: Line 27 : "a1" : missing subscript
C2133: Line 27 : "a1" : unknown size
Code :
int rows;
int columns;
ifstream fObject("inputdata.dat");
fObject>>rows;
fObject>>columns;
char a1[rows][columns];
I am not sure why this is occurring, or if there is a better way to do it.
read a text file and store the file contents into a 2D array?
100 101 102 103 104 105
106 107 108 109 110 111
112 113 114 115 116 117
118 119 120 121 122 123
124 125 126 127 128 131
Here's my code:
const int ROWS = 5;
const int COLS = 6;
int array[ROWS][COLS];
ifstream inputFile;
inputFile.open("table.txt");
[code]....
When i run the program and try and display the array, it doesn't work.
I want to read the contents of a file block (512 bytes) by block using low I/O read statements. Each record is 64 bytes long and has a pre-defined structure. The first 4 bytes are an unsigned integer; the next 20 bytes are ascii text, etc.
I have a buffer which I can access with buf[0] to buf[63] to read the first record and then buf[64] to buf[127] for the second, etc. However, I was wondering how to map a record so that I can refer to an integer as an integer and a float as float, etc. I can't create a struct and move the 64 bytes to it, as I will have alllignment/padding problems.
What is the standard way to deal with records in C?
How can I read contents of a file from the last character? Can I use a loop?
View 10 Replies View RelatedI need a sample program to read contents of any xml file using CPP.
View 2 Replies View RelatedCode:
#include <stdio.h>
#include <stdlib.h>
int main (int argc, char *argv[])
{
char buffer[256];
FILE * myfile;
myfile = fopen("read.txt","r");
[Code]...
I also got an error in printing wherein the data in read.txt is "Hello" newline "World" and my program prints world twice.
Need to correct the errors. i've done so far.
#include<iostream>
#include<fstream>
#include<cstdlib>
#include<iomanip>
using namespace std;
int main() {
ifstream fin; char ch; int size=0;
[Code]...
I have written the following code but i am stuck. Write a program that will prompt the user for a file name and open that file for reading. Print out all the information in the file, numbering each new line of text.
Code:
#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#include <ctype.h>
int main()
{
char line[81], filename[21], c;
int i = 1;
FILE *inFile;
[code]....
am trying to create a service that will try to create a service that will monitor a folder. Whenever a new file gets created, I am trying to read the contents of new file and copy contents (with same file) at a new location.
The problem I am facing is that only first file that gets its name copied and a file created at a new location, but without any contents. The subsequent files do not get created at all.
My Services.cs looks like this:-
public partial class Service1 : ServiceBase
{
public Service1()
{
[Code]....
So I am working on a FUSE filesystem and I currently have the need to load the contents of a text file into an array.
My array initialization looks like: char array[max_entries][PATH_MAX] = {NULL}
The reason I want to pass it by reference is that I want my function to return two values essentially. One a specific char* and the other an array like I initialized. My function proto type looks like:
char* load_meta(char* list[max_entries][PATH_MAX], char* path, int mode);
How I'm trying to call the function:
someChar = load_meta(&array, path_name, 1);
Within the function I try to edit the array by deferenceing it once, like this:
strcpy(*list[i], file_entry); // This seg faults
I am trying to store the contents of a text file into a char array. However the function i am using ifstream member function get(); seems to stop working when fed with certain characters. Is there another solution besides the get() function that will accept all types of characters from files?
char text[1000];
for (int i = 0; i <= textlen; ++i)
{
text[i] = text_in.get();
}
I am trying to store a large text file into an array so I can count the number of characters.
View 2 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].....
called object 'fptr_in' is not a function or function pointer
called object 'fptr_out' is not a function or function pointer
what can i do for the errors?(i mustn't use loop and arrays for the code)
Code:
#include <stdio.h>
void sum_of_2nd_and_3nd( FILE* fptr_in, FILE* fptr_out);
int main()
return 0;
}
void sum_of_2nd_and_3nd( FILE* fptr_in, FILE* fptr_out){
}
[code].....
I am currently writing a password generator in Microsoft Visual Studios 2010 Professional. The section I am having a problem with is the practical password. It is suppose to randomly read 3 words from a text file and then display it in the text box. The program will compile and run but when I hit generate I get "True True True" and not three random words. Then this warning shows up:
Warning C4800: 'char *' : forcing value to bool 'true' or 'false' (performance warning)
//Code is from the form1.h file. I can post the rest of the code if need be but I just included my includes and the problematic section
Code:
#pragma once
#include <cstdlib>
#include <ctime>
#include <stdlib.h>
#include <cmath>
#include <iostream>
#include <iomanip>
[Code] ....
Screenshot of the warnings: [URL] .....
Picture of the output: [URL] ....
Objective of this program is to read binary data from a file and print it.
Code:
#include <stdio.h>
void readFile(void);
int main(){
readFile();
return 0;
[Code] .....
But When I Run This Code First It Print "Error." Then Rest Of The File.Say In My File I Have "I AM HUMAN", It Prints "Error. HUMAN"!!
I Cant Figure Out Whats Wrong In The readFile() Function.It seems right to me.
My professor wants me to write a program that will read from a dat file, and produce an output on the screen based on the file. I don't understand why I am getting this error. I suspect it has something to do with the number of characters I've told it to read.
#include<iostream>
#include<iomanip>
#include<fstream>
#include<assert.h>
#include<string>
using namespace std;
using namespace System;
struct TStudent {
string month[10];
[Code] .....
I noticed I had a 2 beside girl, after I removed it, it still didn't fix my problem.
I am trying to read enormous binary files (10-100GB) and parse their contents a bit at a time. As part of the process I need to get the size of the file in bytes. The simple solution
Code: fseek(file,0,SEEK_END);
size=ftell(file);
fails because the file size overflows the long int type returned by ftell. I need a long long int.
Is there a reasonably efficient way to do this? The good news is that it only needs to be done once. I suppose I could read it one character at a time until I hit the end and keep count, but that just seems inelegant...
I am trying to create an array with the size of the first value of one file wich is the same of the first line because the first line only have one value. Here is how i am trying to do it ...
FILE * fich;
int test;
fich=fopen(nome_ficheiro,"r");
fscanf_s(fich,"%d",&test);
int np=test;
No*aux=primeiro;
[Code] .....
I'm doing a Text-based RPG game and it will include some checkpoints, on those checkpoints the game will save the progress, so I need to write all my variables to a text file and then read them all when the player loads the game.
Some of my variables, like enemyNames, dont have any determined size, they're like this: "int enemyNames[];"
So how do I write an array to a text file without determining a size?
And how do I read them when the player loads the game?
I'm writing a program that stores records into a file and then these records can be printed out. A last name, first name, and score is stored to be exactly 36 characters long (using leading spaces to pad) making it easier to retrieve specific records. For example, three records stored in the file would like like this: (the underscores are simply to illustrate the distance, they are not in the file itself)
_______lastname_______firstname__90__________lname __________fname_100___________last___________first __60
When printed out, the names are formatted as follows:
lastname, firstname: 90
lname, fname: 100
last, first: 60
However, when I print them out this is what I get:
lastname, firstname: 90
lname, fname: 100$
last, first: 60H
For some reason, for any record after the first, an extra character is added to the end. These characters are not in the file, so I was thinking that the array for some reason wasn't being filled completely, (the array is initialized to size 36 and 36 characters are read from the file using fread) so it was printing out a random character assigned to the 36th array position. Except the character never changes, (always a $ for record 2, H for record 3, l for record 4 if i remember) and I've tried reducing the array size or the number of character read and it's the string that gets altered, the random character always remains. I figure the problem must be in the print_records function (appending seems to work no problem). Anyway here is my print records and appending records code.
Code: /*
- Prints a single record stored in the file pointed to by ifp.
*/
void print_record(FILE *ifp, int record) {
[Code]......
After looking online for a string replace function in C and finding so many examples that go through the entire string twice. First round to find how number of occurances of substitute in string, using that to malloc for a new string to include additional space for replace, then going through the search string again to get all but what's to be substituted out. I feel it's kind of silly to go through the string twice. Therefore, I'm trying to implement my own string replace, that only searches through the string for what's to be substituted, once.
Here is my code:
Code:
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
char *strreplace(char * string, char * sub, char * replace);
}
[code]....
Here is the same code, but with execution + some syntax highlighting: Ideone.com | Online C Compiler & Debugging Tool..It works great, until it gets to grabbing whatever remains in the search string after the last found sub. The realloc throws a runtime error:
Code:
*** glibc detected *** ./a.out: realloc(): invalid next size: 0x00011008 ***
Aborted From my understanding, this is from me going outside of the bounds of the heap and using memory I haven't allocated, or using a free'd pointer. I'm not seeing where either of these are happening in my code, and was wondering what the best way to go about figuring out where the error exactly occurs.
I'm finishing up my first semester as a Computer Science major, but I'm struggling with programming.
I need to read a file into a 2D array.
Here is what the file contains (90 characters):
S
R
R
S
R
R
R
R
S
....
Here is my current code:
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
[Code]....
I need to do a program that reads a file, that contains something like this:
8 2 3 4 2
5 6 1 3 4
3 1 4 6 7
7 2 4 1 3
3 2 1 6 8
and put in a array[][] in the program..I did this:
int main(){
using namespace std;
int size=0;
char line[1300];
FILE *file;
char path[50];
int l=0,c=0;
[code].....
But when i print A[3][3], it does not contain the correct value, but I strange value, like -36893488147419103000 .My idea was to pass line by line of the file, including the values that were not " ", to get only the numbers.
Trying to do a homework assignment for a class and how to read a file into an array. I've looked in our book and on several other forums and cant seem to find any examples of this. Below is the assignment I'm working on. I have a shell of the program that I can get to run, but getting a .txt file to read into an array is something I cant seem to figure out how to do.
Write a program to read N data items into two arrays, X and Y, of size 20. Store the product of the corresponding pairs of elements of X and Y in a third array Z, also of size 20. Print a three column table that displays the arrays X, Y, and Z. Then compute and print the square root of the sum of the items in array Z. Compute and print the average of the values in array Z and print all values above the average of array Z. Determine the smallest value in each array using only one function.
Use the two data files named DATAX.TXT and DATAY.TXT.
You must use functions for the reading of the data, computing the average, printing the three column table and printing the values above average.
I can't get the values correctly parsed.
Code:
float **get(int sizeX, int sizeY) /* Allocate the array */ {
float** ary = new float*[sizeX];
for(int i = 0; i < sizeX; ++i)
ary[i] = new float[sizeY];
return ary;
[Code] ....
test.txt (without the comments).
Code:
2 3 // columns and rows of 2D array
0 0
1 1
2 2