C :: Using Fwrite With Text Output

Mar 9, 2013

I have the following code:

Code:
void Plot(int nx, int ny, double x[350], double y[350], double C_new[350][350], int iplot){
int i, j;
char fname[50];
FILE *fp;

[Code]....

I am then taking the generated file and importing it into a plotting program (Techplot360). It would speed up the importing process if I created a binary file instead of a like above. I know that I need to use fwrite but I am unsure how to handle lines like

Code:
fprintf(fp, "TITLE= ABCDEFG_%d
", iplot); and

Code: fprintf(fp, "%f %f %f
", x[i], y[j], T_new[i][j]);

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C :: Using Fwrite And Fread On Structs

Jul 20, 2014

I'm currently working on a program that writes an array of struct to a file and then read back the data from the file to another array of struct. At the bottom is an image of my result.

My goal is to end up with two identical struct arrays but my program fails to do this. My struct have to members: ID and kind (of animals in this case). I declare my first arraystruct africa[] with "monkey" and "giraffe" with their respectively IDnr: 112 and 555. I stream this data to a file and read read them back to the arraystruct get_animal[]. Simply I want the get_animal[] to be identical with the africa[] when the program is over, but that is not so. According to my result(bottom image) it display:

112, monkey (get_animal[0])
112, monkey (get_animal[1])
meaning that get_animal[0] is identical to africa[0] get_animal[1] is also identical to africa[0]

but why? I want get_animal[1] to be identical with africa[1]. meaning I want the result to look like this:

112, monkey
555, giraffe

I've also made the program to print the parameters of my fwrite/fread calls. Why is the 3rd parameter = 1 meaning that only 1 element will be read/written when my program just read/write 2 elements?

Code:

main(){
FILE *fp;
struct animals
{
int id;
char kind[20];
} africa[1] = {{112,"monkey"}, {555,"giraffe"}};
}

[code]....

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C++ :: Fwrite - Calculating Elapsed Time

Jan 24, 2013

I have a question. I would like to actually have some measure of roughly how long it takes to do a fwrite to a drive. When I do the following:

clock_t begin = clock();
unsigned long long size_t = fwrite(send, 1, transfer_size*sizeof(unsigned long long), wpFile);
clock_t end = clock();
double long elapsed_secs = double long(end - begin) / CLOCKS_PER_SEC;

Unfortunately, I don't get any different result for different transfer size!!!

My guess is that the clock_t , once it issues a fwrite command, some how stops its measurement, and it comes back again, when I am already done with fwrite. I do get the almost same measure, whether my transfer size is 32KB Byte or 16MB ! Which I was indeed expecting to see a huge difference. I wouldn't really want the exact real timing measure (well off course it will be nice to know); and all I care about is to see some difference in time whether I am doing KB transfer vs MB transfer.

Some rough measurement required of the actual time being elapsed for fwrite function?

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C++ :: Pointer Of Union And Fwrite Operation

Jul 5, 2013

I have union of pointer.

union {
short *two_int;
int *four_int;
double *eight_real;
char *one_ascii;
// void *v;
};

We have write function which write into file.

fwrite (r.one_ascii, 1, i, outstr);

I found one thing,When we write function, we fill only four int in following way.

r.four_int[0] = x + xoff;
r.four_int[1] = y + yoff;

So my question,we fill four_int but write one_ascii only.As is it union of pointer. So it does not matter. I am using 64bit machine and do not have any issue in 32 bit machine.

For more information: [URL] ....

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C++ :: Fwrite Calculating Elapsed Time

Jan 23, 2013

I would like to actually have some measure of roughly how long it takes to do a fwrite to a drive. When I do the following:

clock_t begin = clock();
unsigned long long size_t = fwrite(send, 1, transfer_size*sizeof(unsigned long long), wpFile);
clock_t end = clock();
double long elapsed_secs = double long(end - begin) / CLOCKS_PER_SEC;

Unfortunately, I don't get any different result for different transfer size!!!

My guess is that the clock_t , once it issues a fwrite command, some how stops its measurement, and it comes back again, when I am already done with fwrite. I do get the almost same measure, whether my transfer size is 32KB Byte or 16MB ! Which I was indeed expecting to see a huge difference.

I wouldn't really want the exact real timing measure (well off course it will be nice to know); and all I care about is to see some difference in time whether I am doing KB transfer vs MB transfer. Any other function that will give me some rough measurement of the actual time being elapsed for fwrite function?

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C :: Weird Characters Popping Up In Fwrite Function

Mar 13, 2013

Code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main() {

[Code]....

this code asks the user to input words/strings until he enters "end."after that, the program must copy the input to a text file named read.txt...I entered 'j' and then 'end' and after that I looked at the read.txt file and here's what's in it.

Output:

Code:
j
; end

some weird characters appeared!! the characters in the text file should only be.

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C :: Fread / Fwrite And Fseek (reverse Of WAV File)

Jun 28, 2013

I am trying to write a function to reverse a wav file. The idea is to copy the header as it is from the begening of the input.wav file to the beginning of the output.wav file. After that i have to take count number of bytes(count = numberChannels * bitsPerSample in the wav i use this is 2*16= 32 bits, 32/8 = 4 bytes). With this code i am trying to copy the header( that's working fine) and then copy 10 samples from the end and put them to the output.wav file(after header not at the beginning).

This is the content of the input file:

The last 4 bytes of the header are bolded.

Code:
52 49 46 46 24 bd 01 00 57 41 56 45 66 6d 74 20
10 00 00 00 01 00 02 00 44 ac 00 00 10 b1 02 00
04 00 10 00 64 61 74 61 00 bd 01 00 00 10 00 10
ff 00 10 00 00 10 00 10 00 00 ff 10 10 10 00 10
00 00 00 10 10 10 10 00 00 00 10 00 10 00 10 ff
00 10 00 00 10 00 ff 00

This is the content of the output file it suppose to have in my example

Code:
52 49 46 46 24 bd 01 00 57 41 56 45 66 6d 74 20
10 00 00 00 01 00 02 00 44 ac 00 00 10 b1 02 00
04 00 10 00 64 61 74 61 00 bd 01 00 10 00 ff 00
00 10 00 00 10 00 10 ff 00 00 10 00 10 10 10 00
00 00 00 10 10 10 00 10 00 00 ff 10 00 10 00 10
ff 00 10 00

Code:
void reverse(char **array) {
int i=0;
word numberChannels;//word is unsigned short int , byte is unsigned char
word bitsPerSample;

[Code] .....

The problem is that (having in mind per sample is 4 bytes) instead of copying 40 bytes it just copies 20

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C++ :: Output 2 Different Text Files

May 22, 2013

So I'm trying to output 2 different text files, one has customer names and the other has items they are selling. I gave each customer an ID and each of their items has the same ID. Only problem is when I try to output it, it only outputs the first item with the same ID. I do not want to display the ID number at all, I think getline would show it so I am not using it.

here's my code

ifstream infile, infile2;
string Fname, Lname, email, item, itemPrice;
int id, itemID;
infile.open("Data.txt");
infile2.open("ItemList.txt");

[Code] .....

The first customer shirt item isn't being outputted. Maybe I'm reading the or comparing the info wrong or just not seeing it.

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C :: Crypt File With XOR Instruction - Fread / Fwrite Segmentation Fault

Jan 21, 2015

I try to crypt file with XOR instruction, by always receive segmentation fault. What's wrong with it?

Code:
#include <stdio.h>
main() {
FILE *fin,*fout;
char buff[40];
int a=0x11;
int i=0;

[Code] ....

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C :: Output Does Not Print On Text File

Jul 19, 2013

In this program I can not print the typed value in the file. The file creation well done but it is an empty file

I press Ctrl +z for EOF

Code:
#include<stdio.h>
int main(void){
FILE *fp;
char ch;
fp=fopen(" Test.txt","w");
printf(" Enter the TEXT

[Code] .....

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C++ :: Program Won't Output Any Information To Text File

May 6, 2013

my program wont output any information to the text file that I have specified it just creates it but it leaves it blank

#include <iostream>
#include<string>
#include<iomanip>
#include <fstream>
using namespace std;
class Carloan

[code]....

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C++ :: Output Unusual Format For Text File

Jul 24, 2013

Bit of a problem, I'm trying to output the data from my code into a particular format to a text file. The format is

y0 y1 y2 y3 y4 y5...yn
z0 0.01 0.2 1
z1 0.4 0 etc...
z2
z3
z4
z5
...
zn

Any pointers?

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C++ :: Writing Output Of While Loop To Text File?

Jul 30, 2014

[URL] when I try to write my output to a file. I am building a life insurance premium calculator with c++. What my calculator does is read in a text file called "policies.txt" containing a number of different policies. 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

And using this, it creates a single premium. Once the calculator calculates the premium of each policy, I want it to write out the premium amount of each policy to a textfile called "output.txt". The problem is that when I check my "output.txt" file, only the premium for the last policy shows up. It only reads:

Premium for Pol4 is 220384
When I want it to read:

Premium for Pol1 is 14101.6
Premium for Pol2 is 14221.2
Premium for Pol3 is 582391
Premium for Pol4 is 220384

How come only the last policy is showing up? and is there any way to make all four policies appear in my output text file? Here is my code:

double ratesmn[86] = {
#include "MaleNonSmoker.txt"
- 1
};

[Code]....

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C++ :: Getting 2 Decimal Places In Output Text File?

Jul 30, 2014

how I can make my output only have 2 decimal places because I want it to be a monetary value. In my code I used this:

cout.setf(ios::fixed);
cout.setf(ios::showpoint);
cout.precision(2);

which worked well at first because on my command prompt screen the numbers had two decimal places and looked liked this:

Premium for Pol1 is $14101.62
Premium for Pol2 is $14221.16
Premium for Pol3 is $582390.50
Premium for Pol4 is $220384.49

However, I also have the program outputting to a textfile called "output.txt" and when I opened this text file the numbers only had one or no decimal places.

Premium for Pol1 is $14101.6
Premium for Pol2 is $14221.2
Premium for Pol3 is $582391
Premium for Pol4 is $220384

How come the code for two decimal places is working for my output to command prompt but not my output to the text file?

Here is my code.

double ratesmn[86] = {
#include "MaleNonSmoker.txt"
- 1
};

[Code].....

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C/C++ :: Read Text File And Display It In Output

Apr 7, 2014

I'm supposed to read a text file and display it in the output. I have it down except my formatting. I just cannot get it to just skip one line rather than multiple. I know why though because my char has a max of 11 and if I put a character lets say mango, it is going to fill in the rest with white spaces. It's supposed to display like this:

Mango
Strawberry
Grapes

But instead I get something like this

Mango

Melon

Grapes

I am using isspace but it's not working.

//source code

#include <iostream>
#include <iomanip>
#include <cstdlib>
#include <cmath>
#include <fstream>
using namespace std;
class CFile

[Code] ....

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C++ :: How To Output Void Function On A Text File

Feb 12, 2013

So I am writing this code that analyzes a file called "analysis.txt" and prints out in an ouput file (called "report.txt") the results of the analysis, i.e.,(the frequency of all alphabet letters present in the file).

I am having trouble with outputing on the file2.

here is what I have:

Code:

#include<iostream>
#include<fstream>
using namespace std;
ifstream file1;

[Code]....

I tried to lose the "<<" after the file 2, but it's still giving me an error. how to output a void function on a text file?

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C++ :: Input / Output Text File Manipulation Not Working

Mar 24, 2013

Why my output screen for this program does not want to stay open. It only opens for a split of a second and it's gone. The program is supposed to take numbers from a input file and display and save the manipulation in the output file. Here is the program.

Code:
#include<iostream>
#include<fstream>
#include<iomanip>
usingnamespace std;

[Code] ....

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C++ :: Grade Calculator - Output With Comment To A Text File

Feb 24, 2013

I am a math teacher who is taking a programming class. My district wants to incorporate some programming tasks into the high school math curricula. I am working on a project to calculate a final grade and output this along with a comment to a text file. The following data is the input that I created:

3 300 100 100 100 .15
4 400 100 98 94 92 .45
3 300 98 100 92 .40

The final grade output results in gibberish.

#include <iostream>
#include <fstream> // For file I/O
#include <string>
#include <iomanip>
#include <cmath>

using namespace std;

[Code] ....

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C++ :: Constructing Random Text Generator - Final Output

Nov 26, 2013

I am constructing a random text generator and i am almost done i just need final output. Here is my coding

#include <iostream>
#include <cstdlib>
#include <ctime>
#include <string>
using namespace std;

const int NUM_FRIENDS = 5;

[Code] ....

This is how the output is supposed to look like

Program Output

== Who Should I Text? ==
Enter seed
Enter friend 0
Enter friend 1
Enter friend 2
Enter friend 3
Enter friend 4
You should text: Cat

These other friends didn't make the cut:
Adam
Bill
Damion
Edward

I can't figure how to output the remaining names.

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C# :: Emails And Phone Numbers - Output List Name Not Text?

Sep 11, 2014

Trying to output a .txt file of names emails and phone numbers, but this only outputs the list name: Email.PersonEntry.

private void button1_Click(object sender, EventArgs e) {
DialogResult result;
string fileName;
//Find and Open File

[Code] ....

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C/C++ :: How To Give A Color To The Text That Displayed In Output Screen

Jan 27, 2013

i am using c++v30.5 version i want red color text in in my output screen . i viewed various site but the result is 0 ,wat to do?

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Visual C++ :: Read Some Text And Output Without Displaying Repeating Words

Sep 8, 2014

I have been given an assignment to make a code to read some text nd display all the words nd the number of times they appear in another file or as output without displaying the repeating words. I made the code but its not giving any output.

#include<iostream>
#include<conio.h>
#include<fstream>
#include<string>
using namespace std;
void read(string);
string x,z,w;

[Code] ....

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C/C++ :: Read All Song Titles From A Text File - Randomly Select And Output?

Apr 19, 2015

So far I have managed to sort songs by their string length in main. The void function is there because i learned how to create it, but it's not being used because I dont know how to use it.

Expanding on main, how would I go about selecting a random song from the array?

#include <fstream>
#include <iomanip>
#include <iostream>
#include <string>
using namespace std;
struct Song {
string song;

[code]....

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C :: File Operations - Fwrite Padding Extra Data In File Compare To Data Provided As Input

Oct 28, 2014

I am trying to write my files to another subfolder . Below is my program.

Code:
cat th6.c
#include <pthread.h>
#include <stdio.h>
#include <string.h>

#define SIZE 8
#define NUMELM 8

[Code] ....

I observe my filename along with directory as text in the new file created in sublfolder. This is output.

[cporgs/apue/threads]: mkdir first
[cporgs/apue/threads]: ./a.out test.txt first
test.txt -- first/test.txt
dfdfdfdfdfdfdf-14
dfdfdfdfdfdfdf-14
in thread test.txt first
[cporgs/apue/threads]: cat first/test.txt
dfdfdfdfdfdfdffirst/test.txt
[cporgs/apue/threads]: cat test.txt
dfdfdfdfdfdfdf

I could not able to get from where this filename and folder is getting added.

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C/C++ :: Program That Opens Text File And Checks Usernames Listed In Text Files?

Jun 5, 2014

I want to make a program that opens a text file and checks the usernames listed in the text files to see if the names are registered on a site such as twitter. How easy would this be to make, what things would I need to know?

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C++ :: Getline - Get Text File And Read Only First 100 Lines Of Text Content

May 31, 2013

I am trying to get text file and read only first 100 lines of the text content using c/c++. how can i do it?

is it something like string line;
getline(stream,line);

??

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