I am having a structure called matrix as shown below to represent a matrix your read from a text file.
struct matrix
{
double mat[30][30]; //content of the matrix mat
int row; //number of row in the matrix mat
int col; ////number of col in the matrix mat
};
Declare 3 variables of structure matrix, m1, m2 and m3 in main to be used as describe below.
Task:
1.Write a function void readFile(char *filename, matrix *m) that will read a matrix from a text file and copy to the structure matrix m.
I 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];
Basically I am to create a program that will read two saved text files; one is [2x4] ~ (matrixA.txt) and another is [4x2] ~ (matrixB.txt). The program is supposed to read both text files, multiply them, and generate an output that will be saved as ~ (matrixC.txt).
C:UsersLeDerpHW1.c: In function `main': HW1.c:27: parse error before `int' //Line 28 C:UsersLeDerpHW1.c: At top level: HW1.c:34: warning: parameter names (without types) in function declaration //35 HW1.c:34: warning: data definition has no type or storage class //35 HW1.c:35: parse error before `for' //37
why I cannot get correct value for the third element in my struct?In the second file where I'm reading from memory I allocate some space. Is this incorrect in some way? I'm running this on a Linux machine.
I just want to know the code of the program: Write code to accept matrix as aurgument and display its multiplication matrix which return its multiplication matrix.
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?
but if the matrix is compressed_matrix type, there's something with it. the error log as below:
Check failed in file boost_1_48_0/boost/numeric/ublas/detail/matrix_assign.hpp at line 1078: detail::expression_type_check (m, cm) terminate called after throwing an instance of 'boost::numeric::ublas::external_logic' what(): external logic Aborted
I'm working on a project for my son. I want to imitate the code for the matrix in CMD using a .bat file.
~note: this is an example of whats going on, not the whole code
:start @set /a bottomlimit = 0 @set /a upperlimit = 2 @set /a result1 = %bottomlimit% + %random% %% (%upperlimit% - %bottomlimit% + 1) if %result1% == "2" set /a result1 = " " <- this is the part that is messing up, it doesnt change the 2 to a blank space and keeps echoing as 2 echo %result1%
I have written code that saves a matrix to a utf-8 file. This code works just fine when invoked from a win32 console app, but if I attempt to use the exact same code by invoking it within a SDI Doc/View Serialize(CArchive& ar), if(ar.IsStoring), it fails, but in a somewhat unusual manner. Namely, the file shows up in the designated directory, but it is an empty file (0 bytes), and the 'Unable to open file' message is seen in Debug config. Note that both the win32 console app and the SDI app are both using a Unicode character set, however, only the SDI app uses the method inside a Serialize(CArchive& ar) method, whereas the win32 console app evokes the save method directly from within _tmain. Why this seemingly illogical disparity occurs.
Here's the template code I have used in innumerable applications to save matrices to a disk file.
Code: namespace TNT { // saves a TNT double matrix, discriminating between real and complex matrices by virtue of the respective file markers, 'MATCALC94R' and 'MATCALC94C'. template <class T> void SaveRealBMatrix(const Matrix<T> &M, string sfilename) { _RPT0(0, "SaveRealBMatrix: "); _RPT1(0, "sfilename =: |%s|
[Code] ....
Here's the code from the SDI document Serialize(CArchive& ar) that fails as described above. Note that m_M is a class member TNT::Matrix<double> m_M that has been verified to exist in the Serialize method.
Why is it reading in nothing for the arrays, and also making the size of the total thing the total number of numbers? It should have a size of 2, not 5.
I was attempting something weired with address to move data around when I discovered that the size of the array is not what I expected. I am passing this structure as &Users to a function that declares it as a void *, then I can deal with chunks of data (memmove) and not have to worry about index or things like that. However...sizeof is returning something I do not understand.
I am trying to write a structure to a file. Example say the structure has two variables x and y . I want to write a function which modifies these variables and stores the modified version on a file. Such that next time I call the function . it has the values from the previous write. Here's an example of my code .
// do some calculations. fwrite(mystruct, sizeof(MYSTRUCT), 1, fp); fclose(fp)
//return some value }
The problem is that each time I run the program it shows the initialized value of the variables and not the value from last write. I guess the write isn't successful because when I open in w+ mode. i get the error file could not be opened and then i have to delete the file and re create it....
I need to write a widget that will implement some matrix functions using data from a text file. The input data will be spreadsheet like and fully determined with complete rows and columns. I need to do the following,
1. populate a data structure with the input data (double) to create matrix x 2. transpose the input data matrix x to create x' 3. multiply x * x' to create a square matrix x'x 4. take the determinant of x'x
This is pretty standard linear algebra, but not something I have done in cpp before. Implementation such as the best data types to use to store each of the three matrices, how they are sized, and what library functions may be available for the matrix functions like transpose, multiply, determinant, etc.
I will be removing each data row from the initial input to observe the effect on the determinant in case that has any effect on program design.
I want to take the informaition from this file and save it into a struct the file conteins name age year (in char) and a grade it is somthing like this
file Nikos Tolis 19 A 8 Iwanna Nikolaou 20 B 9 Kwstas Doukas 20 Β 6 Georgios Pappas 19 A 7 Iwannis Lekatis 20 Β 7 Nikos Ntoumas 19 A 5 Maria Oikonomou 20 B 6 Kwstas Argyrou 19 A 10 Irw Ntouma 20 B 8 Leuteris Doukas 19 A 6
I want to read till i found the '32' the space in ascii here is my code so far
Code: #include<stdio.h> #include<string.h> #include<stdlib.h> struct students { char *name; int age;
My code has no errors. I'm just having problems with getting the grades of the file sorted. grades is not a struct, but is a int inside struct School. Below is what I;m having problems with(this is just the code I started working with,I made a few changes but it didn't work,I have no clue)
void selectionSortG() { Students min; int key; for (int i = 0; i < size; i++){ min = student[i]; key = i; for (int k = i; k < size; k++)