4 files changed, 29 insertions, 21 deletions

diff --git a/core/divelogexportlogic.cpp b/core/divelogexportlogic.cpp
index 926dd461c..017689568 100644
--- a/core/divelogexportlogic.cpp
+++ b/core/divelogexportlogic.cpp
@@ -99,12 +99,15 @@ static void exportHTMLstatistics(const QString filename, struct htmlExportSettin
 			out << "\"AVG_SAC\":\"" << get_volume_string(stats_yearly[i].avg_sac) << "\",";
 			out << "\"MIN_SAC\":\"" << get_volume_string(stats_yearly[i].min_sac) << "\",";
 			out << "\"MAX_SAC\":\"" << get_volume_string(stats_yearly[i].max_sac) << "\",";
-			if ( stats_yearly[i].combined_count )
-				out << "\"AVG_TEMP\":\"" << QString::number(stats_yearly[i].combined_temp / stats_yearly[i].combined_count, 'f', 1) << "\",";
-			else
+			if ( stats_yearly[i].combined_count ) {
+				temperature_t avg_temp;
+				avg_temp.mkelvin = stats_yearly[i].combined_temp.mkelvin / stats_yearly[i].combined_count;
+				out << "\"AVG_TEMP\":\"" << get_temperature_string(avg_temp) << "\",";
+			} else {
 				out << "\"AVG_TEMP\":\"0.0\",";
-			out << "\"MIN_TEMP\":\"" << ( stats_yearly[i].min_temp == 0 ? 0 : get_temp_units(stats_yearly[i].min_temp, NULL)) << "\",";
-			out << "\"MAX_TEMP\":\"" << ( stats_yearly[i].max_temp == 0 ? 0 : get_temp_units(stats_yearly[i].max_temp, NULL)) << "\",";
+			}
+			out << "\"MIN_TEMP\":\"" << ( stats_yearly[i].min_temp.mkelvin == 0 ? 0 : get_temperature_string(stats_yearly[i].min_temp)) << "\",";
+			out << "\"MAX_TEMP\":\"" << ( stats_yearly[i].max_temp.mkelvin == 0 ? 0 : get_temperature_string(stats_yearly[i].max_temp)) << "\",";
 			out << "},";
 			total_stats.selection_size += stats_yearly[i].selection_size;
 			total_stats.total_time.seconds += stats_yearly[i].total_time.seconds;
diff --git a/core/statistics.c b/core/statistics.c
index 13bcc4a97..c7cd213ff 100644
--- a/core/statistics.c
+++ b/core/statistics.c
@@ -24,23 +24,23 @@ stats_t *stats_by_type = NULL;
 
 static void process_temperatures(struct dive *dp, stats_t *stats)
 {
-	int min_temp, mean_temp, max_temp = 0;
+	temperature_t min_temp, mean_temp, max_temp = {.mkelvin = 0};
 
-	max_temp = dp->maxtemp.mkelvin;
-	if (max_temp && (!stats->max_temp || max_temp > stats->max_temp))
-		stats->max_temp = max_temp;
+	max_temp.mkelvin = dp->maxtemp.mkelvin;
+	if (max_temp.mkelvin && (!stats->max_temp.mkelvin || max_temp.mkelvin > stats->max_temp.mkelvin))
+		stats->max_temp.mkelvin = max_temp.mkelvin;
 
-	min_temp = dp->mintemp.mkelvin;
-	if (min_temp && (!stats->min_temp || min_temp < stats->min_temp))
-		stats->min_temp = min_temp;
+	min_temp.mkelvin = dp->mintemp.mkelvin;
+	if (min_temp.mkelvin && (!stats->min_temp.mkelvin || min_temp.mkelvin < stats->min_temp.mkelvin))
+		stats->min_temp.mkelvin = min_temp.mkelvin;
 
-	if (min_temp || max_temp) {
-		mean_temp = min_temp;
-		if (mean_temp)
-			mean_temp = (mean_temp + max_temp) / 2;
+	if (min_temp.mkelvin || max_temp.mkelvin) {
+		mean_temp.mkelvin = min_temp.mkelvin;
+		if (mean_temp.mkelvin)
+			mean_temp.mkelvin = (mean_temp.mkelvin + max_temp.mkelvin) / 2;
 		else
-			mean_temp = max_temp;
-		stats->combined_temp += get_temp_units(mean_temp, NULL);
+			mean_temp.mkelvin = max_temp.mkelvin;
+		stats->combined_temp.mkelvin += mean_temp.mkelvin;
 		stats->combined_count++;
 	}
 }
diff --git a/core/statistics.h b/core/statistics.h
index 9f045c16c..48e75594d 100644
--- a/core/statistics.h
+++ b/core/statistics.h
@@ -28,9 +28,9 @@ typedef struct
 	volume_t max_sac;
 	volume_t min_sac;
 	volume_t avg_sac;
-	int max_temp;
-	int min_temp;
-	double combined_temp;
+	temperature_t max_temp;
+	temperature_t min_temp;
+	temperature_sum_t combined_temp;
 	unsigned int combined_count;
 	unsigned int selection_size;
 	unsigned int total_sac_time;
diff --git a/core/units.h b/core/units.h
index 21f646f79..e124826ce 100644
--- a/core/units.h
+++ b/core/units.h
@@ -110,6 +110,11 @@ typedef struct
 
 typedef struct
 {
+	uint64_t mkelvin; // up to 18446744073 MdegK (temperatures in K are always positive)
+} temperature_sum_t;
+
+typedef struct
+{
 	int mliter;
 } volume_t;