Pulled from upstream master

1 files changed, 79 insertions, 0 deletions

diff --git a/src/c/linearAlgebra/rowcomp/drowcompa.c b/src/c/linearAlgebra/rowcomp/drowcompa.c
new file mode 100644
index 0000000..3161a2d
--- /dev/null
+++ b/src/c/linearAlgebra/rowcomp/drowcompa.c
@@ -0,0 +1,79 @@
+/* Copyright (C) 2017 - IIT Bombay - FOSSEE
+
+ This file must be used under the terms of the CeCILL.
+ This source file is licensed as described in the file COPYING, which
+ you should have received as part of this distribution.  The terms
+ are also available at
+ http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt
+ Author: Sandeep Gupta
+ Organization: FOSSEE, IIT Bombay
+ Email: toolbox@scilab.in
+ */
+
+/* This function is used to find row compression, range */
+
+#include "rowcomp.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include "svd.h"
+#include "norm.h"
+#include "eye.h"
+#include "matrixTranspose.h"
+#include "qr.h"
+
+/* All variable names, are in consideration of scilab documentation. for reference please check the scilab code.*/
+
+double drowcompa(int ninp,double *A,int row,int col,char *flag,double tol,double *w){
+	double rk;
+	double *U;
+	double *S;
+	double *V;
+	double *q,*r,*e;	
+	if(row == 0 || col == 0){
+		w = NULL;		
+		return 0;	
+	}
+	
+	double nA1 = dnorma(A,row,col,1);
+	if(nA1 < sqrt(pow(2,-52))/10){
+		deyea(w,row,col);
+		return 0;	
+	}	
+	if(ninp == 1){
+		flag = "svd";
+		tol = sqrt(pow(2,-52))*nA1;	
+	}
+	else if(ninp == 2){
+		tol = sqrt(pow(2,-52))*nA1;	
+	}
+	else{
+		if(tol < 0){ /* if tolerance is negative */
+			printf(" Wrong values for input argument #: Non-negative scalar expected");		
+		}		
+	}
+	int M = row,N=col;
+	int minMN = min(M,N);
+	char check[3]="qr";
+	//printf(" %s ",flag);
+	if(strcmp(check,flag) == 0){
+		/* calling qr function*/
+		//printf(" * ");		
+		q = (double *)malloc(M*min(M,N)*sizeof(double));
+		r = (double *)malloc(minMN*N*sizeof(double));
+		e = (double *)malloc(N*N*sizeof(double));		
+		rk = dqra(2,4,A,M,N,tol,q,r,e);
+		memcpy(w,q,row*col*sizeof(double));		
+		dtransposea(q,row,row,w);	
+		return rk;					
+	}
+	else{
+		/* svd function type */
+		U = (double *)malloc(row*row*sizeof(double));
+		S = (double *)malloc(row*col*sizeof(double));
+		V = (double *)malloc(col*col*sizeof(double));
+		rk = dsvda(tol,A,row,col,0,4,U,S,V);
+		dtransposea(U,row,row,w);		
+		return rk;	
+	}
+}