Basically, I am inserting data from an ODBC connection into a PostgreSql database using the COPY query, but the COPY query stops and returns this error...
Quote
ERROR: invalid byte sequence for encoding "UTF8": 0x92
CONTEXT: COPY [TableName], line 1: "189572|1-00-1202|1-|00-|1202||AP||1...
STATEMENT: COPY [TableName] FROM STDIN (DELIMITER '|', NULL '')
I'm trying to parse some binary data in the form of an array of bytes and I've come across something that is confusing me related to the representation of data as chars versus ints. It's a bit of a long story, but the byte array contains a mixture of character data and integer data which I' having trouble unravelling. The problem seems to arise from the issue below:
Code:
const char * ch_arr = "abcd";
const unsigned int * ui_arr = (const unsigned int*)ch_arr;
cout << ui_arr[0] << endl;
unsigned int ui = 'a';
ui = ui << 8;
ui |= 'b';
ui = ui << 8;
ui |= 'c';
ui = ui << 8;
ui |= 'd';
cout << ui << endl;
I expected both the output lines to be the same, since they contain the same bytes (I believe), but I get:
Code:
1684234849
1633837924
Is there any open sources available to do the conversion from UTF8 to Unicode(16-bit) and vice versa..
Also i would like to know how can i integrate that library with my code.
I'm trying to understand winsock with c++. Let's assume I have a 2 working applications, one is the client and one the server:
Client: I can enter a command, for example chat or filetransfer, it will then switch into this specific mode where I can enter commands like uploading a file, send a message etc.
Client
Code: ....
while (rc != SOCKET_ERROR) {
printf("
#");
gets(buf);
if (strcmp(buf, "CHAT") == 0){
// start chat mode
[Code] .....
I'm in a recv/send loop and I'm using streams...so basically all the data is being sent/received there. Now, if I want to upload a file, I send a FILETRANSFER String to the server. Then I will probably need another loop that receives file requests from the client. The server will need more details about the file, like the path, name, size...
Now, my question is, what's the best practise for something like that? I'm having problems understand how I can send 3 different values from the server to the client and how he will receive them in the right order store them in variables. And also, after sending something to the server, in some cases, the client will have to wait for the server to answer.
Is there a good example of a similar application?
According to [URL] ....
" char myword[] = { 'H', 'e', 'l', 'l', 'o', ' ' };
char myword[] = "Hello";
In both cases, the array of characters myword is declared with a size of 6 elements of type char: the 5 characters that compose the word "Hello", plus a final null character (' '), which specifies the end of the sequence and that, in the second case, when using double quotes (") it is appended automatically."
However there are examples where word array is declared as :
char myword[] = { 'H', 'e', 'l', 'l', 'o' };
Is syntactically correct?? If yes, what is the size of myword? and does ' ' append by compiler automatically?
And is char myword[] = "abc" same as char myword[] = {'a','b','c',' '} or is it same as char myword[] = {'a','b','c'} ??
I need to take an unknown amount of sorted files and then output any number that is in at least half of them... I know I need to read in the files to a vector and then iterate through them all at the same time looking at the lowest number first and so on. But I am stuck at the point of taking an unknown amount of files and putting them in a container.
This is what I have so far but the vector isn't working and I think I should be putting each file into its own vector.
string get_file(string filename)
{
ifstream in(filename);
if (in)
[Code]....
I got this issue to tackle which consists of using an FIR LPF filter to filter a wav file using C programming.
Till now I managed to tackle the filter part following this link: Implementation of FIR Filtering in C (Part 1) | Shawn's DSP Tutorials (I have my own filter co-efficients which have been produced using FDAtool on MATLAB and some other minor changes have been applied to match my requirements)
Now, the link shown does not compensate for files having a header. I have three wav files which need to be filtered. Thus I need to first extract the data from the header .. this was done using RIFFpad. Now that I have the data
Info from RIFFpad:
fmt -
Offset=20
ID=fmt
[Code].....
I've got this hint to start with: Each audio datasample inside the wav_files can be made up of a number of bytes and these bytes arestored in the little-endian order. Inside your program you have to change this to a big-endian order.
I am writing a application that receives Event messages from a network device the problem I have is that the device sends some message 5 times per tiggered event on two of the events I like to use the rest of the messages are fine I need to create code to filter out the other 4 last messages that get displayed in a textbox the 5 message are identical I have added a timestamp to the sting and noted they are always 1 second apart so the format would be somthing like this:
11:23:01 - x - y
11:23:02 - x - y
11:23:03 - x - y
11:23:04 - x - y
11:23:05 - x - y
What I would like to do something like this, always append the first message to the textbox but ignore or even change the 4 messages that follow 1 second apart from each other that contain - x - y if any other message appears it should still append the text box as well
so the result i would like for the 5 event message as above should end like this:
11:23:01 - x - y
11:23:02 - custome message / ingnore append to textbox
11:23:03 - custome message / ingnore append to textbox
11:23:04 - custome message / ingnore append to textbox
11:23:05 - custome message / ingnore append to textbox
I've been studying the heck out of the boost metafunction libraries. I understand a good deal of what things like varadic functions and integral sequence wrappers are, but I am having a hard time putting everything together to get working functions, such as performing arithmetic operations or functions like that of std::vector.
Here is an example of what I'm talking about:
// Sequences
template<typename T... N> struct seq;
template<typename T, T... N> struct seq_c;
// Integral constant wrapper
template<int T> struct int_
[Code] .....
My knowledge of all of this is pretty scattered and I've really been trying hard to put it all together. Is this correct? How can I apply this and use it to do more?
I'm trying to write code that implements [median filtering] on a two-dimensional array.
Here's an image to illustrate:
The program starts at the beginning of the array. The maximum array size is 100. I know that I can use an array like:
int a[100][100];
to store the input, and that I can iterate over a part of this array using two `for` loops like this:
for(i=0;i<size_filter;i++)
for(j=0;j<size_filter;j++)
temp[i][j]=a[i][j] // not so sure
But how can I make this code loop over the neighbors of every element in the array, calculate their median, and replace the center element with the median?
For some examples of what I'm trying to do, let's say that the input is a 5x5 matrix, so the input size is 5. And I want to run a 3x3 median filter on it, i.e. each element should be replaced by the median of the 3x3 elements surrounding it.
The program starts at the corner index (0,0). For this index, it scans the 3x3 region surrounding it (of which only four indexes actually lie within the input array), which contains the values 0, 0, 1, and 0. The median of these values is 0, so that's what the code should output for this array index.
In the picture below, the number in -band - is the center cell, and the plain * and * numbers are its neighbors within the 3x3 region surrounding it:
-0- *0* 0 0 0
*1* *0* 0 1 0
1 1 0 0 0
0 1 1 0 0
0 0 0 0 0
Here's another example, this time with the center index (0,1):
*0* -0- *0* 0 0
*1* *0* *0* 1 0
1 1 0 0 0
0 1 1 0 0
0 0 0 0 0
This time, the elements in the 3x3 region (excluding those outside the input array) have the values 0, 0, 0, 1, 0, and 0, and again, their median is therefore 0.
Here's yet another example, this time from the middle of the input, at center index (3,2):
0 0 0 0 0
*1* *0* *0* 1 0
*1* -1- *0* 0 0
*0* *1* *1* 0 0
0 0 0 0 0
This time, the elements within the 3x3 region have the values 1, 0, 0, 1, 1, 0, 0, 1, and 1, and their median in therefore 1.
Final example:
<size of array><size filter> <data>
8
3
0 0 0 0 0 0 0 0
0 5 0 0 6 0 0 0
0 0 0 0 0 7 0 0
0 0 0 0 5 0 0 0
0 0 0 5 6 0 0 0
0 0 8 5 5 0 0 0
0 0 0 7 0 0 9 0
0 0 0 0 0 0 0 0
Output:
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 5 5 0 0 0
0 0 0 5 5 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
why filtering don't work??
This is code for load data into dataGridView
private void Izvestaj_Load(object sender, EventArgs e) {
connection.ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:UsersTomyDesktopzadatak2zadatak2fedek_OldVersion(2002-2003).mdb;User Id=admin;Password=;";
dt = new DataTable();
OleDbDataAdapter sda = new OleDbDataAdapter("SELECT korisnici.korisnik,dogadjaji.dogadjaj,Tomislav.Datum
[Code] .....
And this is code for filtering by typing into textbox, when type nothing happening
private void textBox3_TextChanged(object sender, EventArgs e) {
DataView DW2 = new DataView(dt);
DW2.RowFilter = string.Format("dogadjaji.dogadjaj LIKE '%{0}%'", textBox3.Text);
dataGridView1.DataSource = DW2;
[Code] .....
And this is by filtering on dataPickers, range of date, and show me what happens on that dates, but show me exception when click button
private void button1_Click(object sender, EventArgs e) {
if(dateTimePicker1.Value>dateTimePicker2.Value) {
MessageBox.Show("Takav opseg nije moguc. Datum Od mora biti veci od datuma Do.", "Opseg datuma", MessageBoxButtons.OK, MessageBoxIcon.Error);
[code].....
My question is mainly about networks. I wan to implement a simple transparent proxy in C, which will filter the browsed sites according to URL blacklist (check before sending the HTTP request) and keywords in content (check the <meta> in the HTML that was responded).
How can I do this? Listen in a local socket (ex. 8080), set the proxy in my browser and according to the requests that the browser sends to me open a socket with the server, forward the browser's request to the server and forward the server's response to the browser? (Of course by applying filters in the stages where needed.
I've got an application here which connects over the internet to a webserver and sends some json strings. This is all working already.
Now I want to encode one string via mcrypt (because it seemed the easiest library of all) AES and send it over to the other server where it should get decrypted again and checked for validity.
I'll be using this sample code as "starting base". i've found it on the internet:
Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/*
* MCrypt API available online:
[Code] ....
The code works as it is, it encodes my string into a ciphered text and displays the text via the display function to stdout.
From previous projects I know I usually used Base64 for transporting strings via json, but in this example the string is encoded into "%d" - so decimals.. It works too, and I dont care if I send a base64 encoded string or these decimals but how would I calculate back the %d encoded string ? So how would a "undisplay()" class look alike ?
Or maybe there is an easier way to transport the string and re-decode it ?
I'd expect something like:
base64string = base64encode(ciphertext);
...
send base64string to host2
...
at host2:
ciphertext = base64decode(base64string)
...
and then mcrypt_decode that ciphertext...
How to write in DOS encoding using class FILE ?
View 5 Replies View RelatedI am writing a program to zip and unzip files using Huffman Encoding. I have successfully Built my Huffman Tree but I am unable to traverse through it to retrieve code the code for each character in sample files using the GetCode() method.
Here is my zip.cpp file:
#include <iostream>
#include <fstream>
#include <algorithm>
#include <cctype>
#include "huffman.h"
using namespace std;
void CountLetters(int frequency[]);
int main(int argc, char *argv[]) {
[Code] ....
Specifically I am having trouble with the following segment in zip.cpp where I want to go through my built tree and print out each character and it's associated ascii value using the GetCode() method in huffman.cpp
cout << " Here are the codes: "<< endl;
for(char ch = char(0); ch <= char(255); ch++)
//for(int i= 1; i < 256; i++ )
{ //int x = (char) i;
if(mytree.inTree('*'))
[Code] ....
I'm new to C++ and involving encoding and decoding text from text files. When I enter a file in the program just stalls.
#include <iostream >
#include <iomanip>
#include <string>
#include <cstring>
#include <fstream>
using namespace std;
char getmenuselection (char m);
{Code] .....
I am writing a porgram which includes encoding and decoding a message.Now I am doing the encoding part.
The goal is to encode a message using similar approach as Caesar Cipher. But instead of alphabets, I am going to use the entire ASCII code of total 128 codes to be the base.
And it is not a simple shifting, it is a rotation. This means if you want to shift 4 units from char <DEL>, it will come back to the first code in ASCII Code which is at dec 0 char <NUL> and starts the shifting again. It won't jump if the limit of ASCII Code is reached.
Here we've got 7 different malls' names and I am going to encode them with a shift n. I think n is free to set, so here I just set it as 5. This is also called the key.
I have written something and I think it should work, but after all it doesn't. And I don't get what is wrong.
Here is my program:
#include <iostream>
using namespace std;
const int NUMBER_OF_MALLS = 7;
const int MALL_NAME_LENGTH = 13;
const int NAME_SIZE = MALL_NAME_LENGTH + 1;
void encode(int key, char plain[], int length, char encoded[]) {
for (int i = 0; i < MALL_NAME_LENGTH; i++)
[code].....
Note that I am not going to use other libraries, just <iostream>.
I'm transferring a unicode string from one program to another with UTF-8 encoding.
Program that is sending:
Code:
// Convert path
std::wstring_convert<std::codecvt_utf8<wchar_t>> utf8_converter;
CString arg = L" /PATH="" + CString(utf8_converter.to_bytes(path).c_str()) + L""";
Program that is retrieving:
Code:
// Restore original path
std::wstring_convert<std::codecvt_utf8<wchar_t>> utf8_converter;
std::wstring path = utf8_converter.from_bytes( argument );
Everything has worked fine, until running on a Japanese edition of Windows.
The "byte path" then looks something like "C:¥Users¥d✝?✝a ,?¥AppData¥Local¥Temp¥file.txt".
"from_bytes()" will throw an std::range_error exception "bad conversion".
The program works fine when working with Japenese writing inside paths in the English edition.
What could be causing the "bad conversion"?
I have a char *pch that points to an integer digit 1 or 2 or ... 9. To get the character that's 1 less, instead of converting to int, minus 1, then converting back to char, I tried (*pch -1) and that seemed to work. I suppose that's because the particular character encoding on my system is such that the digits are encoded in the same order and spacing as the integers they represent. So the question is does this "convenience" feature hold true for all character encoding systems?
View 10 Replies View RelatedI tried to answer the question myself and came up with an example.
#include<iostream>
using namespace std;
class A {
public:
int a;
A(int aa) : a(aa) { }
~A() { cout<<"~A()
[code]....
why statements (*) and (**) work ? Since the object a gets destroyed, shouldn't rA be invalid ? Or this is just undefined behavior ?
I am getting this error in lines that involve "ch[_]" in lines 27, 28, 29, 33, 42, 43, 44, and 48, heres the code:
Code:
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>
struct integer{
int* digits;
int size;
[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.
The exercise consists on 3 procedures. We get the information from a .txt like these:
01/03/2011 A
02/03/2011 F
03/03/2011 C
04/03/2011 T
(...)
Simulating a Videoclub database where the letters stand for the type of movie (A=Action, T=Terror, C=Comedy, ...) and the dates they were rented.
a) How many movies from one specific genre have been rented more than 'n' times? The genre and the value 'n' must be entered by the user.
b) How many movies and which genres belong to a certain date? The date must be entered by the user.
c) Print a list that shows the number of times a movie from each genre has been rented.
So far this is what I've got:
Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAX 100
typedef struct {
int dia,mes, any;
char genere;
[Code] ....
But right now, my main problem is that I can't even debug because i get an error in line 97 --> while (llista[i][j] != EOF) <-- saying "invalid operands to binary != (have 'lloguer' and 'int').
I've tried to cast (int) before "llista[i][j]" but it says that I'm already supposed to get an integer from that.
I catch an exception and want to log it on the console. This works as exepcted, but Valgrind shows me a set of invalid reads.
Here the code of the catch-block:
} catch(HGL::IOException &e) {
logError(e);
}
The signature of the logDebug is: BasicLogger &operator<<(const std::exception &e);
Now valgrind shows me 4 errors like that:
==20943== Invalid read of size 1
==20943== at 0x402C658: strlen (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==20943== by 0x41554DD: std::basic_ostream<wchar_t, std::char_traits<wchar_t> >& std::operator<< <wchar_t, std::char_traits<wchar_t> >(std::basic_ostream<wchar_t, std::char_traits<wchar_t> >&, char const*) (in /usr/lib/i386-linux-gnu/libstdc++.so.6.0.16)
[Code] .....
Generally I dislike invalid read in my code, even if they are harmless like in that case.
If I don't pass a reference, but a copy of the exception, I don't get this invalid reads, but also loose all information, because of the implicit upcasting.
Why I get the illegal read, resp. why std::wstring is deleting it on the way to the <<-operator?
Basically the whole purpose of this program is to prompt the user to use a calculator. Choices 1-6 are valid, but I want to set it up where selecting any other number outside of 1-6 to be Invalid, and will display an 'Invalid Choice' message, and then go back to the main menu.... The main program does work properly, it's the 'Invalid' setup that is giving me problems
Code:
#include <iostream>
#include <iomanip>
using namespace std;
[Code].....
I wanna know why the program doesnt show "Invalid Letter Entered" when i enter any letter other than A S D or M
//Processing the data
if (letter== 'A'||'S'||'M'||'D')// checking Add, subtract, multiply or divide {
if (letter== 'A')//Adding the integers
cout<<"Adding two integers = "<<first + second<<endl;
else if (letter== 'S')//Subtracting the integers {
[code]......