From 7350184904d50385c89002307c2a4a5f5eef107c Mon Sep 17 00:00:00 2001
From: Raffaele <raffio98@gmail.com>
Date: Thu, 13 Jan 2022 16:16:56 +0100
Subject: [PATCH] first implementations by rdgarce

---
 lina.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 lina.h |  8 +++----
 2 files changed, 73 insertions(+), 5 deletions(-)

diff --git a/lina.c b/lina.c
index b86096a..8b9c1bd 100644
--- a/lina.c
+++ b/lina.c
@@ -1,2 +1,70 @@
-#import <lina.h>
+#include "lina.h"
 
+// Evaluate the dot product C = A*B where C is of size m by l, A is m by n and B is n by l.
+// NOTE: C can't be the same pointer of A or B.
+void lina_dot(double **A, double **B, double **C, unsigned int m, unsigned int n, unsigned int l){
+
+    //Control for the sanity of the inputs:
+    //C must point to a different memory than A and B
+    if(C == A || C == B)
+        //Implement some Cozis-like-good-way method for error signaling
+        return;
+
+    //Actual dot
+    //Iteration on A's rows
+    for(int i=0; i < m;i++){
+        
+        double pos = 0;
+
+        //Iteration on B's collumns
+        for(int k=0; k < l; k++){
+
+            //Iteration on the single B collumn for executing the product of sum
+            for(int j=0; j < n; j++){
+
+            pos = pos + A[i][j] * B[j][k];
+
+            }
+
+            //The usage of a support variable 'pos' is for safety purpose (non-zero C matrix)
+            C[i][k] = pos;
+
+        }
+        
+    }
+
+}
+
+// Evaluate C = A + B where A,B,C are m by n.
+// NOTE: C can be the same location of A or B.
+void lina_add(double **A, double **B, double **C, unsigned int m, unsigned int n){
+
+    for(int i=0;i<m;i++){
+
+        for(int j=0;j<n;j++){
+            C[i][j] = A[i][j] + B[i][j];
+        }
+    }
+
+}
+
+// Evaluate B = k*A where A and B are m by n matrices.
+// NOTE: B can be the same location of A.
+void lina_scale(double **A, double **B, double k, unsigned int m, unsigned int n){
+
+    for(int i=0;i<m;i++){
+
+        for(int j=0;j<n;j++){
+            B[i][j] = k * A[i][j];
+        }
+    }
+
+}
+
+// Evaluate B = A^t (the transpose of A) where A is m by n.
+// NOTE: B can be the same location of A.
+void lina_transpose(double **A, double **B, unsigned int m, unsigned int n){
+
+    
+
+}
\ No newline at end of file
diff --git a/lina.h b/lina.h
index 04f5bdc..013ee73 100644
--- a/lina.h
+++ b/lina.h
@@ -1,16 +1,16 @@
 
 // Evaluate the dot product C = A*B where C is of size m by l, A is m by n and B is n by l.
 // NOTE: C can't be the same pointer of A or B.
-void lina_dot(double *A, double *B, double *C, unsigned int m, unsigned int n, unsigned int l);
+void lina_dot(double **A, double **B, double **C, unsigned int m, unsigned int n, unsigned int l);
 
 // Evaluate C = A + B where A,B,C are m by n.
 // NOTE: C can be the same location of A or B.
-void lina_add(double *A, double *B, double *C, unsigned int m, unsigned int n);
+void lina_add(double **A, double **B, double **C, unsigned int m, unsigned int n);
 
 // Evaluate B = k*A where A and B are m by n matrices.
 // NOTE: B can be the same location of A.
-void lina_scale(double *A, double *B, double k, unsigned int m, unsigned int n);
+void lina_scale(double **A, double **B, double k, unsigned int m, unsigned int n);
 
 // Evaluate B = A^t (the transpose of A) where A is m by n.
 // NOTE: B can be the same location of A.
-void lina_transpose(double *A, double *B, unsigned int m, unsigned int n);
\ No newline at end of file
+void lina_transpose(double **A, double **B, unsigned int m, unsigned int n);
\ No newline at end of file