Initial data commit

Task/Multiple-regression/FreeBASIC/multiple-regression.basic

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+Const N = 14, M = 2, Q = 3    ' number of points and M.R. polynom degree
+
+Dim As Double X(0 to N) = {1.47,1.50,1.52,1.55,1.57, _
+1.60,1.63,1.65,1.68,1.70,1.73,1.75,1.78,1.80,1.83}              ' data points
+Dim As Double Y(0 to N) = {52.21,53.12,54.48,55.84,57.20, _
+58.57,59.93,61.29,63.11,64.47,66.28,68.10,69.92,72.19,74.46}    ' data points
+Dim As Double S(N), T(N)        ' linear system coefficient
+Dim As Double A(M, Q)           ' sistem to be solved
+Dim As Integer i, k, j, fila, columna
+Dim as Double z
+
+For k = 0 To 2*M
+    S(k) = 0 : T(k) = 0
+    For i = 0 To N
+        S(k) += X(i) ^ k
+        If k <= M Then T(k) += Y(i) * X(i) ^ k
+    Next i
+Next k
+
+' build linear system
+For fila = 0 To M
+    For columna = 0 To M
+        A(fila, columna) = S(fila+columna)
+    Next columna
+    A(fila, columna) = T(fila)
+Next fila
+
+Print "Linear system coefficents:"
+For i = 0 To M
+    For j = 0 To M+1
+        Print Using "######.#"; A(i,j);
+    Next j
+    Print
+Next i
+
+For j = 0 To M
+    For i = j To M
+        If A(i,j) <> 0 Then Exit For
+    Next i
+    If i = M+1 Then
+        Print !"\nSINGULAR MATRIX '"
+        Sleep: End
+    End If
+    For k = 0 To M+1
+        Swap A(j,k), A(i,k)
+    Next k
+    z = 1 / A(j,j)
+    For k = 0 To M+1
+        A(j,k) = z * A(j,k)
+    Next k
+    For i = 0 To M
+        If i <> j Then
+            z = -A(i,j)
+            For k = 0 To M+1
+                A(i,k) += z * A(j,k)
+            Next k
+        End If
+    Next i
+Next j
+
+Print !"\nSolutions:"
+For i = 0 To M
+    Print Using "  #####.#######"; A(i,M+1);
+Next i
+
+Sleep