Adding and modify many useful function

in their header file:
-blh2enu.h
-xyz2blh.h
-rahcal.h
-deg2dms.h
-degRrad.h

deg2dms.h

@@ -0,0 +1,34 @@
+#ifndef _DEG2DMS_H_
+#define _DEG2DMS_H_
+
+#include<stdlib.h>
+#include<math.h>
+
+typedef struct
+{
+    double D;
+    double M;
+    double S;    
+}deg2dms, *pdeg2dms;
+
+/* -------------------------------------------------------------------------- */
+/// @brief 将十进制的度数转换为度分秒形式
+/// @param deg2dms 结构体传递参数
+/// @param D 要转换度数
+/// @return 返回自定义结构体包含度，分，秒成员                      
+/* -------------------------------------------------------------------------- */
+pdeg2dms DEG2DMS(pdeg2dms deg2dms,
+                 double D)
+{
+    deg2dms = (pdeg2dms)malloc(sizeof(pdeg2dms));
+    int sig = D / fabs(D);//符号判断
+    deg2dms->D = (int)(D);//转换为度分秒
+    deg2dms->M = (int)((D - deg2dms->D) * 60);//分秒去除符号格式
+    deg2dms->S = (int)(((D - deg2dms->D) * 60 - deg2dms->M) * 60);
+    deg2dms->M  = deg2dms->M * sig;
+    deg2dms->S  = deg2dms->S * sig;
+
+    return deg2dms;
+}
+
+#endif