modify the name by removing "_" in macro TEST/TEST_F

modify the comment by moving name and date behind the function name
replace self-difined PI by the macro M_PI defined in math.in

Author: pxlxingliang

source/module_base/math_integral.h

@@ -14,30 +14,30 @@ class Integral
     ~Integral();
 
     /**
-     * @brief simpson integral. Peize Lin accelerate 2017-10-02
+     * @brief simpson integral.
      * 
-     * @param mesh [in] mhe number of grid points (should be odd)
+     * @param mesh [in] number of grid points (should be odd)
      * @param func [in] function to be integrated
      * @param rab [in] a list of interval
      * @param asum [out] the final integral value
      */
-    static void Simpson_Integral
-    (
+    static void Simpson_Integral  // Peize Lin accelerate 2017-10-02
+    (    
         const int mesh,
         const double * const func,
         const double * const rab,
         double &asum
     );
 
     /**
-     * @brief simpson integral. Peize Lin accelerate 2017-10-02
+     * @brief simpson integral. 
      * 
-     * @param mesh [in] mhe number of grid points (should be odd)
+     * @param mesh [in] number of grid points (should be odd)
      * @param func [in] function to be integrated
      * @param dr [in] interval
      * @param asum [out] the final integral value
      */
-	static void Simpson_Integral
+	static void Simpson_Integral  //Peize Lin accelerate 2017-10-02
 	(
 		const int mesh,
 		const double * const func,
@@ -46,15 +46,15 @@ class Integral
 	);
 
     /**
-     * @brief simpson integral. Peize Lin add 2016-02-14.
+     * @brief simpson integral. 
      *  
      * 
-     * @param mesh [in] mhe number of grid points 
+     * @param mesh [in] number of grid points 
      * @param func [in] function to be integrated
      * @param rab [in] a list of interval
      * @param asum [out] a list of integral value. asum[i] = integral from 0 to i. The max index of asum is an even (mesh-1 or mesh).
      */
-    static void Simpson_Integral_0toall
+    static void Simpson_Integral_0toall  //Peize Lin add 2016-02-14.
     (
         const int mesh,
         const double * const func,
@@ -63,14 +63,14 @@ class Integral
     );
 
     /**
-     * @brief simpson integral. Peize Lin add 2016-02-14.
+     * @brief simpson integral. 
      * 
-     * @param mesh [in] mhe number of grid points 
+     * @param mesh [in] number of grid points 
      * @param func [in] function to be integrated 
      * @param rab [in] r(i) * dr(i)/di * di or (b-a)/2n 
      * @param asum [out] a list of integral value. sum[i] = integral from i to mesh-1. 
      */
-    static void Simpson_Integral_alltoinf
+    static void Simpson_Integral_alltoinf //Peize Lin add 2016-02-14.
     (
         const int mesh,
         const double * const func,

source/module_base/test/math_integral_test.cpp

@@ -3,9 +3,10 @@
 
 #include<math.h>
 
-#define PI 3.14159265358979
 #define doublethreshold 1e-12
 
+
+
 /************************************************
 *  unit test of class Integral
 ***********************************************/
@@ -19,7 +20,7 @@
  * 
  */
 
-class Simpson_Integral_sinx : public testing::Test
+class SimpsonIntegralSinx : public testing::Test
 {
     /**
      * test the integral of sinx between [0,PI],
@@ -31,7 +32,7 @@ class Simpson_Integral_sinx : public testing::Test
     double*     func;
     double*     rab;
     int         mesh = 10001;
-    double      dr   = PI/(mesh-1);
+    double      dr   = M_PI/(mesh-1);
     double      asum;
     double*     asumlist;
     double      expectvalue = 2.0;
@@ -44,7 +45,7 @@ class Simpson_Integral_sinx : public testing::Test
 
         for (int i=0;i<mesh;i++)
         {
-            func[i] = sin(PI*i/(mesh-1));
+            func[i] = sin(M_PI*i/(mesh-1));
             rab[i] = dr;
         }
     }
@@ -57,21 +58,23 @@ class Simpson_Integral_sinx : public testing::Test
     }
 };
 
-TEST_F(Simpson_Integral_sinx,Simpson_Integral_rab)
+
+
+TEST_F(SimpsonIntegralSinx,SimpsonIntegralRab)
 {
     ModuleBase::Integral::Simpson_Integral(mesh,func,rab,asum);
     EXPECT_NEAR(asum,expectvalue,doublethreshold);
     EXPECT_DEATH(ModuleBase::Integral::Simpson_Integral(mesh-1,func,rab,asum),"");
 }
 
-TEST_F(Simpson_Integral_sinx,Simpson_Integral_dr)
+TEST_F(SimpsonIntegralSinx,SimpsonIntegralDr)
 {
     ModuleBase::Integral::Simpson_Integral(mesh,func,dr,asum);
     EXPECT_NEAR(asum,expectvalue,doublethreshold);
     EXPECT_DEATH(ModuleBase::Integral::Simpson_Integral(mesh-1,func,dr,asum),"");
 }
 
-TEST_F(Simpson_Integral_sinx,Simpson_Integral_0toall)
+TEST_F(SimpsonIntegralSinx,SimpsonIntegral0toall)
 {
     int halfmesh = round(mesh/2);
     ModuleBase::Integral::Simpson_Integral_0toall(mesh,func,rab,asumlist);
@@ -82,7 +85,7 @@ TEST_F(Simpson_Integral_sinx,Simpson_Integral_0toall)
 }
 
 
-TEST_F(Simpson_Integral_sinx,Simpson_Integral_alltoinf)
+TEST_F(SimpsonIntegralSinx,SimpsonIntegralAlltoinf)
 {
     int halfmesh = round(mesh/2);
     ModuleBase::Integral::Simpson_Integral_alltoinf(mesh,func,rab,asumlist);