--- a/scripts/sparse/treeplot.m
+++ b/scripts/sparse/treeplot.m
@@ -41,13 +41,13 @@
       if (nargin > 2)
         edge_style = edge_s;
         if (nargin > 1) 
-	  if (length (findstr (node_s, "*")) == 0
-	      && length (findstr (node_s, "+")) == 0
-	      && length (findstr (node_s, "x")) == 0)
-	    node_style = [node_s, "o"];
-	  else
-	    node_style = node_s;
-	  endif
+          if (length (findstr (node_s, "*")) == 0
+              && length (findstr (node_s, "+")) == 0
+              && length (findstr (node_s, "x")) == 0)
+            node_style = [node_s, "o"];
+          else
+            node_style = node_s;
+          endif
         endif
       endif
 
@@ -72,13 +72,13 @@
       stop = zeros (1, num_nodes+1);
       for i = 1:num_nodes+1
         start(i) = pos;
-	xhelp(i) = pos;
-	pos += num_children(i);
-	stop(i) = pos;
+        xhelp(i) = pos;
+        pos += num_children(i);
+        stop(i) = pos;
       endfor
       for i = 1:num_nodes        
         vec_of_child(xhelp(tree(i)+1)) = i;  
-	xhelp(tree(i)+1) = xhelp(tree(i)+1)+1;
+        xhelp(tree(i)+1) = xhelp(tree(i)+1)+1;
       endfor
 
       ## The number of "parent" (actual) node (it's descendants will be
@@ -106,57 +106,57 @@
 
       ## The top of the stack.
       while (par_number != -1)
-	if (start(par_number+1) < stop(par_number+1))
-	  idx = vec_of_child(start(par_number+1):stop(par_number+1)-1);
-	else
-	  idx = zeros (1, 0);
-	endif
+        if (start(par_number+1) < stop(par_number+1))
+          idx = vec_of_child(start(par_number+1):stop(par_number+1)-1);
+        else
+          idx = zeros (1, 0);
+        endif
         ## Add to idx the vector of parent descendants.
-	stk = [stk; [idx', ones(fliplr(size(idx)))*par_number]];
-	## Add to stack the records relevant to parent descandant s.
-	if (par_number != 0)
-	  skelet = [skelet; ([ones(size(idx))*par_number; idx])(:)];
-	endif
+        stk = [stk; [idx', ones(fliplr(size(idx)))*par_number]];
+        ## Add to stack the records relevant to parent descandant s.
+        if (par_number != 0)
+          skelet = [skelet; ([ones(size(idx))*par_number; idx])(:)];
+        endif
 
-	## If there is not any descendant of "parent node":
-	if (stk(end,2) != par_number)
-	  left_most++;
+        ## If there is not any descendant of "parent node":
+        if (stk(end,2) != par_number)
+          left_most++;
           x_coordinate_r(par_number) = left_most;           
-	  max_ht = min (max_ht, level);
+          max_ht = min (max_ht, level);
           if (length(stk) > 1 && find ((shift(stk,1)-stk) == 0) > 1
-	      && stk(end,2) != stk(end-1,2))
-	    ## Return to the nearest branching the position to return
-	    ## position is the position on the stack, where should be
-	    ## started further search (there are two nodes which has the
-	    ## same parent node).
+              && stk(end,2) != stk(end-1,2))
+            ## Return to the nearest branching the position to return
+            ## position is the position on the stack, where should be
+            ## started further search (there are two nodes which has the
+            ## same parent node).
             position = (find ((shift(stk(:,2),1)-stk(:,2)) == 0))(end) + 1;
             par_number_vec = stk(position:end,2);
             ## The vector of removed nodes (the content of stack form
-	    ## position to end).
+            ## position to end).
             skelet = [skelet; flipud(par_number_vec)];
             level += length (par_number_vec);
-	    ## The level have to be decreased.
+            ## The level have to be decreased.
             x_coordinate_r(par_number_vec) = left_most;
             stk(position:end,:) = [];
-          endif	
-       	  ## Remove the next node from "searched branch".
-	  stk(end,:) = [];
-	  ## Choose new "parent node".
+          endif 
+          ## Remove the next node from "searched branch".
+          stk(end,:) = [];
+          ## Choose new "parent node".
           par_number = stk(end,1);
-	  ## If there is another branch start to search it.
-	  if (par_number != -1)
-	    skelet = [skelet; stk(end,2); par_number];
-            y_coordinate(par_number) = level;	
-	    x_coordinate_l(par_number) = left_most + 1;
-	  endif
-	else
+          ## If there is another branch start to search it.
+          if (par_number != -1)
+            skelet = [skelet; stk(end,2); par_number];
+            y_coordinate(par_number) = level;   
+            x_coordinate_l(par_number) = left_most + 1;
+          endif
+        else
           ## There were descendants of "parent nod" choose the last of
-	  ## them and go on through it.
+          ## them and go on through it.
           level--;
-	  par_number = stk(end,1);
-	  y_coordinate(par_number) = level;     
-	  x_coordinate_l(par_number) = left_most + 1;
-	endif
+          par_number = stk(end,1);
+          y_coordinate(par_number) = level;     
+          x_coordinate_l(par_number) = left_most + 1;
+        endif
       endwhile
 
       ## Calculate the x coordinates (the known values are the position
@@ -169,37 +169,37 @@
 
       hold_is_on = ishold ();
       unwind_protect
-	hold ("on");
+        hold ("on");
 
-	## Plot grah nodes.
-	plot (x_coordinate, y_coordinate, node_style);
+        ## Plot grah nodes.
+        plot (x_coordinate, y_coordinate, node_style);
 
-	## Helping command - usable for plotting edges
-	skelet = [skelet; 0];
+        ## Helping command - usable for plotting edges
+        skelet = [skelet; 0];
 
-	## Draw graph edges.
-	idx = find (skelet == 0);
+        ## Draw graph edges.
+        idx = find (skelet == 0);
 
-	## Plot each tree component in one loop.
-	for i = 2:length(idx)
-	  ## Tree component start.
-	  istart = idx(i-1) + 1;
-	  ## Tree component end.
-	  istop = idx(i) - 1;
-	  if (istop - istart < 1)                          
-	    continue;
-	  endif
-	  plot (x_coordinate(skelet(istart:istop)),
-		y_coordinate(skelet(istart:istop)), edge_style)
-	endfor
+        ## Plot each tree component in one loop.
+        for i = 2:length(idx)
+          ## Tree component start.
+          istart = idx(i-1) + 1;
+          ## Tree component end.
+          istop = idx(i) - 1;
+          if (istop - istart < 1)                          
+            continue;
+          endif
+          plot (x_coordinate(skelet(istart:istop)),
+                y_coordinate(skelet(istart:istop)), edge_style)
+        endfor
 
-	## Set axis and graph size.
-	axis ([0.5, left_most+0.5, max_ht-0.5, num_nodes-0.5], "nolabel");
+        ## Set axis and graph size.
+        axis ([0.5, left_most+0.5, max_ht-0.5, num_nodes-0.5], "nolabel");
 
       unwind_protect_cleanup
-	if (! hold_is_on)
-	  hold ("off");
-	endif
+        if (! hold_is_on)
+          hold ("off");
+        endif
       end_unwind_protect
       
     endif