diff --git a/src/subroutines.f90 b/src/subroutines.f90
index 6efb97e..e8c365b 100644
--- a/src/subroutines.f90
+++ b/src/subroutines.f90
@@ -186,15 +186,26 @@ module subroutines
             pos=box_bd(2*i-1)
         else if ((index(pos_string,'-') > 0).and.(index(pos_string,'inf')>0)) then 
             !Now extract the number we are reducing from infinity
-            read(pos_string(index(pos_string,'-')+1:), *, iostat=iospara) pos
+            if(index(pos_string,'inf') < index(pos_string,'-')) then 
+                read(pos_string(index(pos_string,'-')+1:), *, iostat=iospara) pos
+            else
+                read(pos_string(1:index(pos_string,'-')-1), *, iostat=iospara) pos
+            end if
             pos = box_bd(2*i) - pos
         else if ((index(pos_string,'+') > 0).and.(index(pos_string,'inf')>0)) then 
             !Now extract the number we are reducing from infinity
-            read(pos_string(index(pos_string,'+')+1:), *, iostat=iospara) pos
-            pos = box_bd(2*i-1) + pos
+           if(index(pos_string,'inf') < index(pos_string,'-')) then 
+                read(pos_string(index(pos_string,'+')+1:), *, iostat=iospara) pos
+            else
+                read(pos_string(1:index(pos_string,'+')-1), *, iostat=iospara) pos
+            end if
         else if ((index(pos_string,'*') > 0).and.(index(pos_string,'inf')>0)) then 
             !Now extract the number we are reducing from infinity
-            read(pos_string(index(pos_string,'*')+1:), *, iostat=iospara) pos
+           if(index(pos_string,'inf') < index(pos_string,'-')) then 
+                read(pos_string(index(pos_string,'*')+1:), *, iostat=iospara) pos
+            else
+                read(pos_string(1:index(pos_string,'*')-1), *, iostat=iospara) pos
+            end if
             pos = (box_bd(2*i)-box_bd(2*i-1))*pos
         else
             read(pos_string, *, iostat=iospara) pos