diff --git a/tsgqc_GUI.m b/tsgqc_GUI.m
index 4d1c0c655d545b8036b4b207ea60a059c015faee..fe3b8c9fb09e0936bfc846041b9cc3170fe822f6 100644
--- a/tsgqc_GUI.m
+++ b/tsgqc_GUI.m
@@ -44,7 +44,7 @@ function tsgqc_GUI
         ];
     addpath( p, '-END' );
     rehash;
-    
+
     % Screen limits for the GUI
     % -------------------------
     set(0,'Units','normalized');
@@ -745,18 +745,18 @@ function tsgqc_GUI
                 % round positive latitude and Longitude toward zero
                 % -------------------------------------------------
                 ind = find(tsg.LATITUDE > 0);
-                lat(ind) = fix(tsg.LATITUDE(ind));
+                lat(ind) = fix(tsg.LATITUDE(ind)) + 0.5;
                 
                 ind = find(tsg.LONGITUDE > 0);
-                lon(ind) = fix(tsg.LONGITUDE(ind));
+                lon(ind) = fix(tsg.LONGITUDE(ind)) + 0.5;
                 
                 % rounds negative latitude and Longitudeto the nearest lowest integers
                 % ---------------------------------------------------------------------
                 ind = find(tsg.LATITUDE <= 0);
-                lat(ind) = floor(tsg.LATITUDE(ind));
+                lat(ind) = floor(tsg.LATITUDE(ind)) + 0.5;
                 
                 ind = find(tsg.LONGITUDE <= 0);
-                lon(ind) = floor(tsg.LONGITUDE(ind));
+                lon(ind) = floor(tsg.LONGITUDE(ind)) + 0.5;
                 
                 % Calculates differences between adjacent elements of X.
                 % 0 if adajacent latitude or longitude are equal
@@ -774,7 +774,7 @@ function tsgqc_GUI
                 temp = tsg.TEMP_TSG( ind );
                 psal = tsg.PSAL( ind );
 
-                % Get Climatology, a tester et verifier
+                % Get Climatology
                 %           LATX(80)  = -0.5 et LATX(81)  = 0.5
                 %           LONX(180) = -0.5 et LONX(181) = 0.5
                 % ----------------
@@ -784,8 +784,8 @@ function tsgqc_GUI
                 std_temp=zeros(size(ind));
                 std_psal=zeros(size(ind));                
                 for i=1:length(ind)
-                  ilat = find(tsg.LEVITUS.WOA01_LATX == floor(lat2(i))+0.5);
-                  ilon = find(tsg.LEVITUS.WOA01_LONX == floor(lon2(i))+0.5);
+                  ilat = find(tsg.LEVITUS.WOA01_LATX == lat2(i));
+                  ilon = find(tsg.LEVITUS.WOA01_LONX == lon2(i));
                   mean_temp(i) = tsg.LEVITUS.WOA01_MEAN_TEMP(ilat,ilon,1);
                   mean_psal(i) = tsg.LEVITUS.WOA01_MEAN_PSAL(ilat,ilon,1);
                   std_temp(i)  = tsg.LEVITUS.WOA01_STD_TEMP(ilat,ilon,1);