added support for the modified PCA in concat mode

meldata.cc

@@ -303,11 +303,22 @@ namespace Melodic{
       	  			std_pca(tmpData, RXweight, Corr, pcaE, pcaD);
 	  				calc_white(pcaE, pcaD, order, newWM, newDWM);
 				}else{
-					std_pca(whiteMatrix*tmpData, RXweight, Corr, pcaE, pcaD);
-					calc_white(pcaE, pcaD, order, newWM, newDWM);		
-					newDWM=(dewhiteMatrix*newDWM);
-					newWM=(newWM*whiteMatrix);
-				}
+					if(!opts.dr_pca.value()){
+						std_pca(whiteMatrix*tmpData, RXweight, Corr, pcaE, pcaD);
+						calc_white(pcaE, pcaD, order, newWM, newDWM);		
+						newDWM=(dewhiteMatrix*newDWM);
+						newWM=(newWM*whiteMatrix);
+					}
+					else{
+						Matrix tmp1, tmp2;
+						tmp1 = whiteMatrix * alldat;  
+						tmp1 = remmean(tmp1,2) * tmpData.t();  
+						tmp2 = pinv(tmp1);  
+						std_pca(tmp1 * tmpData, RXweight, Corr, pcaE, pcaD);
+						calc_white(pcaE, pcaD, order, newWM, newDWM);		
+						newDWM=(tmp2*newDWM);
+						newWM=(newWM * tmp1);
+					}
 				DWM.push_back(newDWM);
 				WM.push_back(newWM);
 				tmpData = newWM * tmpData;

meloptions.h

@@ -55,7 +55,8 @@ class MelodicOptions {
   	Option<string> pca_est;
   	Option<bool>   joined_whiten;
   	Option<bool>   joined_vn;
-		Option<float>	 vn_level;
+	Option<bool>   dr_pca;
+	Option<float>	 vn_level;
   	Option<int>    numICs;
   	Option<string> approach;
   	Option<string> nonlinearity;
@@ -191,6 +192,9 @@ class MelodicOptions {
    joined_vn(string("--sep_vn"), true,
    	   string("switch off joined variance nomalisation"), 
        false, no_argument),
+   dr_pca(string("--mod_pca"), false,
+	   string("switch on modified PCA for concat ICA"),
+	   false, no_argument, false),
    vn_level(string("--vn_level"), float(2.3),
 	   string("variance nomalisation threshold level (Z> value is ignored)"), 
 	   false, requires_argument, false),
@@ -391,6 +395,7 @@ class MelodicOptions {
 	    options.add(pca_est);
 	    options.add(joined_whiten);
 	    options.add(joined_vn);
+		options.add(dr_pca);
 	    options.add(vn_level);
 	    options.add(numICs);
 	    options.add(approach);