1 files changed, 12 insertions, 1 deletions

diff --git a/src/parameters.cpp b/src/parameters.cpp
index 2e2758a..f08736b 100644
--- a/src/parameters.cpp
+++ b/src/parameters.cpp
@@ -1,5 +1,5 @@
-#include "calendar.h"
 #include "parameters.h"
+#include "calendar.h"
 #include <utility>
 using namespace std;
 
@@ -221,3 +221,14 @@ double parameter::moon_longitude(double t) {
         L -= 360;
     return L;
 }
+
+double parameter::getHourAngle(double julianKiloTime, double longitude,
+                               double latitude, double alpha) {
+    double t = 100 * 365.25 * julianKiloTime;
+    // 该时刻的格林尼治恒星时
+    double GST = 6.697374558 + 2400.051336 * t + 0.000025862333 * t * t -
+                 0.000000001722222 * t * t * t;
+    return GST * M_PI / 12 + longitude - alpha;
+    // double GST = 241.654320 + 360.9856473840 * t * 1000 * 36525;
+    // return GST * M_PI / 180 + longitude - alpha;
+}
\ No newline at end of file