# Tutorial: Matrix Structure This tutorial explains how to use a Matrix structure for solving linear equations. For the assignment, you must use the given Matrix structure and follow instructions for saving and modifying the data. ## Tutorial 1: Preparation of Matrix Structure ### Download 1. Download data files: * [NP\_Matrix\_TemplateCode\_Data.zip](https://github.com/ykkimhgu/NumericalProg-student/tree/main/tutorial/TU_Matrix_C_Program) 2. Download tutorial source and header files: * [TU\_matrixTemplate\_student.cpp](https://github.com/ykkimhgu/NumericalProg-student/tree/main/tutorial/TU_Matrix_C_Program) * [myMatrix\_student\_2026.h](https://github.com/ykkimhgu/NumericalProg-student/tree/main/include) * [myMatrix\_student\_2026.cpp](https://github.com/ykkimhgu/NumericalProg-student/tree/main/include) ### Create Data Folder (상대경로 방법, recommended) Create a data folder in the workspace name the folder as `NP_Data` * **..\repos\NP\NP\_Data** For each assignment, create the assignment folder and save the dataset. Example: Assignment999 * **\NP\NP\_Data\Assignment999** For this tutorial, unzip the downloaded data files and copy them under the data folder `Assignment999` ![image](https://github.com/user-attachments/assets/9a848a9d-80b2-4615-a5bc-c71a8154f991) ### Create Data Folder (절대경로 방법, not recommended <-- for TA only) Create a folder in **C:\\** Drive and name the folder as `NP_Data` * **C:\NP\_Data** For each assignment, create the assignment folder and save the dataset. Example: Assignment999 * **C:\NP\_Data\Assignment999** For this tutorial, unzip the downloaded data files and copy them under the data folder `Assignment999` ![NP\_Matrix\_Data\_Example\_img](https://github.com/ykkimhgu/NumericalProg-student/blob/main/docs/NP_Matrix_Data_example.png?raw=true) ### Create Project Create a new empty project in Visual Studio Community. Name the project as **TU\_MatrixTemplate** * **e.g ) C:\Users\yourID\source\repos\NP\tutorial\TU\_MatrixTemplate** Create a new C/C++ source file for main() * Name the source file as `TU_matrixTemplate.cpp` * Use the downloaded source code : TU\_matrixTemplate\_student.cpp Save the downloaded library header files in your `\include\` folder * [myMatrix\_student.h, myMatrix\_student.cpp](https://github.com/ykkimhgu/NumericalProg-student/tree/main/include) * Write your name in the comment section * Re-name the header files as: * myMatrix.h, myMatrix.cpp > Then, you need to change in `myMatrix.cpp` as `#include "myMatrix.h"` ## Tutorial 2: Create and Modify Dataset For each assignment, create the assignment folder and save the dataset. * Example: Assignment000 * `\NP\NP_Data\Assignment000` Use the **text file** and **file name** as instructed in each assignment. > You must use the same name for the **text files** as instructed. Otherwise, it will not be graded Example: ``` - Announcement for Assignment3 - [File Path] ../../NP_Data/Assignment3 // C:/NP_Data/Assignment3 [File Name] Q1. matrix A : prob1_matA vector b : prob1_vecb Q2. matrix A : prob2_matA vector b : prob2_vecb Q3. matrix A : prob3_matA vector b : prob3_vecb ``` #### **How to modify in the data file** * Change Row : **Enter** * Change Column: **Tap** #### Example : Type: * 1 tab 3 tab -2 tab 4 enter .... 3 tab -1 tab 6 tab 2 ctrl+s (저장) ![matrix\_text\_file\_example](https://github.com/ykkimhgu/NumericalProg-student/blob/main/docs/matrix_text_file.png?raw=true) For Vector, type: * -11 enter 6 enter -9 enter 15 ctrl+s (저장) ![vector\_text\_file\_example](https://github.com/ykkimhgu/NumericalProg-student/blob/main/docs/vector_text_file.png?raw=true) ## Tutorial 3: Using Matrix Structure Library ### Matrix structure library Provided library: `myMatrix.h` ```cpp // myMatrix.h typedef struct { double** at; int rows, cols; }Matrix; // Create Matrix with specified size extern Matrix createMat(int _rows, int _cols); // Copy matrix extern Matrix copyMat(Matrix _A); // Free a memory allocated matrix extern void freeMat(Matrix _A); // Create a matrix from a text file extern Matrix txt2Mat(std::string _filePath, std::string _fileName); //// Print matrix extern void printMat(Matrix _A, const char* _name); // Matrix addition extern Matrix addMat(Matrix _A, Matrix _B); // .... ``` #### Example Code ```cpp /*==========================================================================*/ /* Variables declaration & initialization */ /*--------------------------------------------------------------------------*/ // Option 1: Read from datafile Matrix matA = txt2Mat(path, "prob1_matA"); Matrix vecb = txt2Mat(path, "prob1_vecb"); // Option 2: Create an empty Matrix or Vector int rows = 4; int cols = 4; Matrix matC = createMat(rows, cols); // Option 3: Create a zero matrix with specific size Matrix matD = zeros(matA.rows, matA.cols); /*==========================================================================*/ /* Accessing, modifying Matrix */ /*--------------------------------------------------------------------------*/ // Example: Accessing each element in Matrix for (int i = 0; i < matA.rows; i++) for (int j = 0; j < matA.cols; j++) matC.at[i][j] = matA.at[i][j]; printMat(matA, "matA"); // Exmaple: Applying your NP algorithm Matrix matAdd = addMat(matA, matC); printMat(matAdd, "matU + matA"); /*==========================================================================*/ /* Deallocate memory */ /*==========================================================================*/ freeMat(matA); freeMat(vecb); ``` ### What to change for Assignment 1. Initially, change the assignment number for `#define ASGN` * DO NOT modify other code lines ```cpp #include "myMatrix.h" #define ASGN 999 // enter your assignment number #define EVAL 0 // [※ DO NOT EDIT !!!] int main(int argc, char* argv[]) { /* [※ DO NOT EDIT !!!] Resources file path setting for evaluation */ //std::string path = "C:/NP_Data/Assignment" + std::to_string(ASGN) + "/"; std::string path = "../../NP_Data/Assignment" + std::to_string(ASGN) + "/"; #if EVAL path += "eval/"; #endif ... ``` 2. Read data text files. You must use the given file names. 3. Then, apply your numerical programming algorithm. ```cpp /*==========================================================================*/ /* Variables declaration & initialization */ /*--------------------------------------------------------------------------*/ /* - You can change the variable names */ /* - However, you must use the specified txt file name */ /*==========================================================================*/ Matrix matA = txt2Mat(path, "prob1_matA"); Matrix vecb = txt2Mat(path, "prob1_vecb"); Matrix matU = txt2Mat(path, "prob1_matU"); Matrix vecd = txt2Mat(path, "prob1_vecd"); Matrix vecx_true = txt2Mat(path, "prob1_vecx_true"); // Your Code goes Here // Your Code goes Here /*==========================================================================*/ /* Apply your numerical method algorithm */ /*==========================================================================*/ Matrix matAdd = addMat(matA, matU); // example code // Your Code goes Here // Your Code goes Here // ... ``` 4. Prints vector or matrix results. You have to give a brief description for each print. ```cpp /*==========================================================================*/ /* Print your results */ /*==========================================================================*/ printMat(matA, "Problem 1, Matrix A"); printMat(vecb, "Problem 1, Vector b"); ``` 5. Free memory allocated to a matrix. * Even if you omit the free process, the code will work. However, it can cause memory leaks. ```cpp /*==========================================================================*/ /* Deallocate memory */ /*==========================================================================*/ freeMat(matA); freeMat(vecb); ``` *** ## Tutorial 4: More Exampls and Template Code You can download tutorial source files: * [TU\_matrixExample.cpp](https://github.com/ykkimhgu/NumericalProg-student/tree/main/tutorial/TU_Matrix_C_Program) ```c++ #include #include #include #include "../../../include/myMatrix_student.h" void myNPfunc(Matrix L, Matrix U, Matrix Ain); Matrix myNPfunc2(Matrix Ain, Matrix bin); int main(int argc, char* argv[]) { printf("\n**************************************************"); printf("\n| Various Initialization methods |"); printf("\n**************************************************\n"); // Method 1: Initialize matrix Z from array int M = 3; int dim = 1; double z[3] = { 1, 2, 3 }; Matrix Zinit = arr2Mat(z, M, dim); Matrix Z = createMat(M, 1); copyMatrix(Z, Zinit); printMat(Z, "Z is "); // Method 2: Initialize by a constant int N = 3; Matrix Ain = createMat(N, N); initMat(Ain, 1); // Method 3: Initialize with Zero matrix Matrix L = zeros(Ain.rows, Ain.cols); Matrix U = zeros(Ain.rows, Ain.cols); printf("\n**************************************************"); printf("\n| Example Code 1 |"); printf("\n**************************************************\n"); printMat(Ain, "A is "); printMat(L, "L is "); printMat(U, "U is "); // Your Algorithm myNPfunc(L, U, Ain); printMat(Ain, "Ain is (after) "); printMat(L, "L is (after)"); printMat(U, "U is (after)"); printf("\n**************************************************"); printf("\n| Example Code 2 |"); printf("\n**************************************************\n"); // Initialize matrix Ain initMat(Ain, 1); Matrix Xin = zeros(Ain.cols, 1); Matrix Bin = zeros(Ain.rows, 1); printMat(Ain, "A is "); printMat(Bin, "Bin is "); // Your Algorithm Xin = myNPfunc2(Ain, Bin); printMat(Xin, "Xin is (after)"); printMat(Ain, "Ain is (after) "); freeMat(Z); freeMat(Ain); freeMat(L); freeMat(U); freeMat(Ain); freeMat(Xin); freeMat(Bin); system("pause"); return 0; } void myNPfunc(Matrix L, Matrix U, Matrix Ain) { // Initialize Output Matrix: Ain--> U copyMatrix(U, Ain); initMat(L, 0); // Modify Mout by your NP algorithm U.at[1][0] = 30; U.at[2][0] = 40; L.at[0][0] = 6; L.at[1][0] = 7; L.at[2][0] = 8; // This also changes Ain in main() !!! // You may NOT want to modify Ain. Ain.at[0][0] = 10; // This does not changes Ain in main() // For input A, make a Copy to prevent modification Matrix Atemp = zeros(Ain.rows, Ain.cols); copyMatrix(Atemp, Ain); Atemp.at[0][0] = 100; return; } Matrix myNPfunc2(Matrix Ain, Matrix bin) { // Initialize Output Matrix int n = Ain.cols; Matrix Xout = zeros(n, 1); // Modify Mout by your NP algorithm Xout.at[1][0] = 11; Xout.at[2][0] = 12; // This also changes Ain in main() !!! // You may NOT want to modify Ain. Ain.at[0][0] = 10; // This does not changes Ain in main() // For input A, make a Copy to prevent modification Matrix Atemp = zeros(Ain.rows, Ain.cols); copyMatrix(Atemp, Ain); Atemp.at[0][0] = 100; return Xout; } ``` *** ## Exercise and Assignment Declare and define the following functions in `myMatrix.h` and `myMatrix.cpp` ```cpp // Create matrix of all zeros extern Matrix zeros(int _rows, int _cols); // Create matrix of all ones extern Matrix ones(int _rows, int _cols); // Create identity matrix extern Matrix eye(int _rows, int _cols); // Matrix subtraction extern Matrix subMat(Matrix _A, Matrix _B); // Multiply matrix A and matrix B extern Matrix multMat(Matrix _A, Matrix _B); // Multiply matrix A with a scalar k extern Matrix smultMat(Matrix _A, double _k); // Create Transpose matrix extern Matrix transpose(Matrix _A); ``` *** ## Tutorial 5: Modifying and Returning Matrix by a Function (2026) You can download tutorial source files: * [TU\_matrixExample1.cpp](https://github.com/ykkimhgu/NumericalProg-student/tree/main/tutorial/TU_Matrix_C_Program) ```c++ #include #include #include #include "../../include/myMatrix_student.h" Matrix myFunc(Matrix Z); void myFunc2(Matrix Z, Matrix Mout); void printAddress(Matrix Z, const char* name); int main(int argc, char* argv[]) { int M = 3; int dim = 1; double z[3] = { 1, 2, 3 }; printf("\n**************************************************"); printf("\n| Intiialization |"); printf("\n**************************************************\n"); // Initialize matrix Z Matrix Zinit = arr2Mat(z, M, dim); Matrix Z = createMat(M, 1); copyMatrix(Z, Zinit); printMat(Z, "Z is "); printAddress(Z, "Z is "); printf("\n**************************************************"); printf("\n| Example 1 (return Matrix) |"); printf("\n**************************************************\n"); Matrix M_out = zeros(Z.rows, Z.cols); printMat(M_out, "M_out is (before)"); printAddress(M_out, "M_out "); M_out = myFunc(Z); printf("\n[Main()]\n\r"); printMat(M_out, "M_out is (after)"); printAddress(M_out, "M_out (after) "); printMat(Z, "Z is (after) "); printf("\n**************************************************"); printf("\n| Example 2 (void) |"); printf("\n**************************************************\n"); // Initialize matrix Z copyMatrix(Z, Zinit); Matrix M_out2 = zeros(Z.rows, Z.cols); printMat(M_out2, "M_out2 is (before)"); printAddress(M_out2, "M_out2 "); myFunc2(Z, M_out2); printf("\n[Main()]\n\r"); printMat(M_out2, "M_out2 is (after)"); printAddress(M_out2, "M_out2 (after) "); printMat(Z, "Z is (after) "); freeMat(Z); freeMat(M_out); freeMat(M_out2); system("pause"); return 0; } Matrix myFunc(Matrix Z) { // Initialize Output Matrix int n = Z.rows; Matrix Mout = zeros(n, 1); Matrix Ztemp = zeros(n, 1); printf("\n[myFunc_Q1]\n\r"); printAddress(Z, "Z in myFunc"); printAddress(Mout, "Mout in myFunc "); // Copy Matrix copyMatrix(Mout,Z); printAddress(Mout, "Mout in myFunc (after)"); // Copy Matrix copyMatrix(Ztemp, Z); // Modify Mout by your NP algorithm Mout.at[1][0] = 20; // This also changes Z in main() Z.at[0][0] = 10; // This does not changes Z in main() Ztemp.at[0][0] = 100; return Mout; } void myFunc2(Matrix Z, Matrix Mout) { printf("\n[myFunc_Q2]\n"); printAddress(Z, "Z in myFunc2"); printAddress(Mout, "Mout in myFunc2"); // Initialize Output Matrix by Copying Z--> Mout copyMatrix(Mout, Z); printAddress(Mout, "Mout in myFunc (after)"); // Modify Mout by your NP algorithm Mout.at[1][0] = 20; // This also changes Z in main() Z.at[0][0] = 10; return; } void printAddress(Matrix Z, const char* name) { printf("%s\n\r", name); //printf(" &Matrix.at[0][0] : %p\n\n", &Z.at[0][0]); //printf(" &Matrix struct : %p\n\n\r", &Z); printf(" Matrix.at : %p\n", Z.at); } ``` *** *** ## Tutorial 4: Modifying and Returning Matrix by a Function (\~ 2025) ## Case: Return Type is `Matrix` An error occurs when `freeMat` is used inside a function. ### Option 1. Using copyVal ```c++ #include #include #include #include "../../include/myMatrix.h" Matrix myFunc_Q1(Matrix Z); void printAddress(Matrix Z, const char* name); int main(int argc, char* argv[]){ int M = 3; int dim = 1; double z[3] = { 1, 2, 3 }; Matrix Z = arr2Mat(z, M, dim); Matrix Z_out = zeros(Z.rows, Z.cols); printf("\n**************************************************"); printf("\n| Question 1. (Matrix, copyVal) |"); printf("\n**************************************************\n"); printMat(Z_out, "Z_out is (before)"); Z_out = myFunc_Q1(Z); printMat(Z_out, "Z_out is (after)"); freeMat(Z); freeMat(Z_out); system("pause"); return 0; } Matrix myFunc_Q1(Matrix Z) { int n = Z.rows; Matrix F = zeros(n, 1); printf("\n[myFunc_Q1]\n"); printAddress(Z, "Z in myFunc_Q1"); printAddress(F, "F in myFunc_Q1 "); copyVal(Z, F); printAddress(F, "F in myFunc_Q1 (after)"); return F; } void printAddress(Matrix Z, const char* name) { printf("%s\n", name); printf(" &Matrix struct : %p\n", &Z); printf(" Matrix.at : %p\n", Z.at); printf(" &Matrix.at[0][0] : %p\n\n", &Z.at[0][0]); } ``` ### Option 2. Using copyMat ```c++ #include #include #include #include "../../include/myMatrix.h" Matrix myFunc_Q2(Matrix Z); void printAddress(Matrix Z, const char* name); int main(int argc, char* argv[]){ int M = 3; int dim = 1; double z[3] = { 1, 2, 3 }; Matrix Z = arr2Mat(z, M, dim); Matrix Z_out1 = zeros(Z.rows, Z.cols); printf("\n**************************************************"); printf("\n| Question 2. (Matrix, copyMat) |"); printf("\n**************************************************\n"); printMat(Z_out1, "Z_out1 is (before)"); Z_out1 = myFunc_Q2(Z); printMat(Z_out1, "Z_out1 is (after)"); freeMat(Z); freeMat(Z_out1); system("pause"); return 0; } Matrix myFunc_Q2(Matrix Z) { int n = Z.rows; Matrix F = zeros(n, 1); printf("\n[myFunc_Q2]\n"); printAddress(Z, "Z in myFunc_Q2"); printAddress(F, "F in myFunc_Q2 "); F= copyMat(Z); printAddress(F, "F in myFunc_Q2 (after)"); return F; } void printAddress(Matrix Z, const char* name) { printf("%s\n", name); printf(" &Matrix struct : %p\n", &Z); printf(" Matrix.at : %p\n", Z.at); printf(" &Matrix.at[0][0] : %p\n\n", &Z.at[0][0]); } ``` * There is no issue when using either `copyVal` or `copyMat`. ## Case: Return type is `void` ### Option 1. Using copyVal * The structure is copied, but the internal pointer remains the same. Can apply modification. ```c++ #include #include #include #include "../../include/myMatrix.h" void myFunc_Q3(Matrix Z, Matrix U); void printAddress(Matrix Z, const char* name); int main(int argc, char* argv[]){ int M = 3; int dim = 1; double z[3] = { 1, 2, 3 }; Matrix Z = arr2Mat(z, M, dim); Matrix Z_out2 = zeros(Z.rows, Z.cols); printf("\n**************************************************"); printf("\n| Question 3. (void, copyVal) |"); printf("\n**************************************************\n"); printMat(Z_out2, "Z_out2 is (before)"); myFunc_Q3(Z, Z_out2); printMat(Z_out2, "Z_out2 is (after)"); freeMat(Z); freeMat(Z_out2); system("pause"); return 0; } void myFunc_Q3(Matrix Z, Matrix U) { printf("\n[myFunc_Q3]\n"); printAddress(U, "U in myFunc_Q3"); // Copy U copyVal(Z, U); printAddress(U, "U in myFunc_Q3 (after)"); return; } void printAddress(Matrix Z, const char* name) { printf("%s\n", name); printf(" &Matrix struct : %p\n", &Z); printf(" Matrix.at : %p\n", Z.at); printf(" &Matrix.at[0][0] : %p\n\n", &Z.at[0][0]); } ``` ### Option 2. Using copyMat (Need to pass by Pointer) * The address of the Matrix is sent to the function. * Need to use as a pointer in the passed Function. ```c++ #include #include #include #include "../../include/myMatrix.h" void myFunc_Q5(Matrix *Z, Matrix *U); void printAddress(Matrix Z, const char* name); int main(int argc, char* argv[]){ int M = 3; int dim = 1; double z[3] = { 1, 2, 3 }; Matrix Z = arr2Mat(z, M, dim); Matrix Z_out4 = zeros(Z.rows, Z.cols); printf("\n**************************************************"); printf("\n| Question 5. (void, copyMat) |"); printf("\n**************************************************\n"); printMat(Z_out4, "Z_out4 is (before)"); myFunc_Q5(&Z, &Z_out4); printMat(Z_out4, "Z_out4 is (after)"); freeMat(Z); freeMat(Z_out4); system("pause"); return 0; } void printAddress(Matrix Z, const char* name) { printf("%s\n", name); printf(" &Matrix struct : %p\n", &Z); printf(" Matrix.at : %p\n", Z.at); printf(" &Matrix.at[0][0] : %p\n\n", &Z.at[0][0]); } void myFunc_Q5(Matrix *Z, Matrix *U) { printf("\n[myFunc_Q5]\n"); printf("&U (address of pointer variable) : %p\n", (void*)&U); printf("U (points to Matrix struct) : %p\n", (void*)U); printf("U->at (data pointer) : %p\n\n", (void*)U->at); *U = copyMat(*Z); printf("&U (address of pointer variable) : %p\n", (void*)&U); printf("U (points to Matrix struct) : %p\n", (void*)U); printf("U->at (data pointer) : %p\n\n", (void*)U->at); return; } ``` ### Option 3. Using copyMat (Does not return modified Matrix) * The Matrix is copied and sent to the function. * Does not return the modified Matrix to 'main' ```c++ #include #include #include #include "../../include/myMatrix.h" void myFunc_Q4(Matrix Z, Matrix U); void printAddress(Matrix Z, const char* name); int main(int argc, char* argv[]){ int M = 3; int dim = 1; double z[3] = { 1, 2, 3 }; Matrix Z = arr2Mat(z, M, dim); Matrix Z_out3 = zeros(Z.rows, Z.cols); printf("\n**************************************************"); printf("\n| Question 4. (void, copyMat) |"); printf("\n**************************************************\n"); printMat(Z_out3, "Z_out3 is (before)"); myFunc_Q4(Z, Z_out3); printMat(Z_out3, "Z_out3 is (after)"); freeMat(Z); freeMat(Z_out3); system("pause"); return 0; } void printAddress(Matrix Z, const char* name) { printf("%s\n", name); printf(" &Matrix struct : %p\n", &Z); printf(" Matrix.at : %p\n", Z.at); printf(" &Matrix.at[0][0] : %p\n\n", &Z.at[0][0]); } void myFunc_Q4(Matrix Z, Matrix U) { printf("\n[myFunc_Q4]\n"); printAddress(U, "U in myFunc_Q4"); U = copyMat(Z); printAddress(U, "U in myFunc_Q4 (after)"); return; } ``` ## Other Options ```c++ #include #include #include #include "../../include/myMatrix_student.h" Matrix myFunc_Q1(Matrix Z); Matrix myFunc_Q2(Matrix Z); void myFunc_Q3(Matrix Z, Matrix U); void myFunc_Q4(Matrix Z, Matrix U); void myFunc_Q5(Matrix Z, Matrix* U); void printAddress(Matrix Z, const char* name); int main(int argc, char* argv[]) { int M = 3; int dim = 1; double z[3] = { 1, 2, 3 }; Matrix Z = arr2Mat(z, M, dim); printMat(Z, "Z is "); printf("\n**************************************************"); printf("\n| Question 1. (Matrix, copyVal) |"); printf("\n**************************************************\n"); printAddress(Z, "Z is "); Matrix Z_out = zeros(Z.rows, Z.cols); printMat(Z_out, "Z_out is (before)"); printAddress(Z_out, "Z_out "); Z_out = myFunc_Q1(Z); printMat(Z_out, "Z_out is (after)"); printAddress(Z_out, "Z_out (after) "); printf("\n**************************************************"); printf("\n| Question 2. (Matrix, copyMat) |"); printf("\n**************************************************\n"); printAddress(Z, "Z is "); Matrix Z_out1 = zeros(Z.rows, Z.cols); printMat(Z_out1, "Z_out1 is (before)"); printAddress(Z_out1, "Z_out1 "); Z_out1 = myFunc_Q2(Z); printMat(Z_out1, "Z_out1 is (after)"); printAddress(Z_out1, "Z_out1 (after) "); printf("\n**************************************************"); printf("\n| Question 3. (void, copyVal) |"); printf("\n**************************************************\n"); Matrix Z_out2 = zeros(Z.rows, Z.cols); printMat(Z_out2, "Z_out2 is (before)"); printAddress(Z_out2, "Z_out2 "); myFunc_Q3(Z, Z_out2); printMat(Z_out2, "Z_out2 is (after)"); printAddress(Z_out2, "Z_out2 (after) "); printf("\n**************************************************"); printf("\n| Question 4. (void, copyMat) |"); printf("\n**************************************************\n"); printAddress(Z, "Z is "); Matrix Z_out3 = zeros(Z.rows, Z.cols); printMat(Z_out3, "Z_out3 is (before)"); printAddress(Z_out3, "Z_out3 "); myFunc_Q4(Z, Z_out3); printMat(Z_out3, "Z_out3 is (after)"); printAddress(Z_out3, "Z_out3 (after) "); printf("\n**************************************************"); printf("\n| Question 5. (void, copyMat) |"); printf("\n**************************************************\n"); printAddress(Z, "Z is "); Matrix Z_out4 = zeros(Z.rows, Z.cols); printMat(Z_out4, "Z_out4 is (before)"); printAddress(Z_out4, "Z_out4 "); myFunc_Q5(Z, &Z_out4); printMat(Z_out4, "Z_out4 is (after)"); printAddress(Z_out4, "Z_out4 (after) "); freeMat(Z); freeMat(Z_out); freeMat(Z_out1); freeMat(Z_out2); freeMat(Z_out3); freeMat(Z_out4); system("pause"); return 0; } Matrix myFunc_Q1(Matrix Z) { int n = Z.rows; Matrix F = zeros(n, 1); printf("\n[myFunc_Q1]\n"); printAddress(Z, "Z in myFunc_Q1"); printAddress(F, "F in myFunc_Q1 "); copyVal(Z, F); printAddress(F, "F in myFunc_Q1 (after)"); return F; } Matrix myFunc_Q2(Matrix Z) { int n = Z.rows; Matrix F = zeros(n, 1); printf("\n[myFunc_Q2]\n"); printAddress(Z, "Z in myFunc_Q2"); printAddress(F, "F in myFunc_Q2 "); F = copyMat(Z); printAddress(F, "F in myFunc_Q2 (after)"); return F; } void myFunc_Q3(Matrix Z, Matrix U) { printf("\n[myFunc_Q3]\n"); printAddress(U, "U in myFunc_Q3"); // Copy U copyVal(Z, U); printAddress(U, "U in myFunc_Q3 (after)"); return; } void myFunc_Q4(Matrix Z, Matrix U) { printf("\n[myFunc_Q4]\n"); printAddress(U, "U in myFunc_Q4"); U = copyMat(Z); printAddress(U, "U in myFunc_Q4 (after)"); return; } void myFunc_Q5(Matrix Z, Matrix* U) { printf("\n[myFunc_Q5]\n"); printf("Matrix->at : %p\n\n", (void*)U->at); *U = copyMat(Z); printf("Matrix->at) : %p\n\n", (void*)U->at); return; } void printAddress(Matrix Z, const char* name) { printf("%s\n\r", name); //printf(" &Matrix.at[0][0] : %p\n\n", &Z.at[0][0]); //printf(" &Matrix struct : %p\n\n\r", &Z); printf(" Matrix.at : %p\n", Z.at); } ``` *** --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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