cfd_constants.h

include 函数库。。。。 真是没什么好说的 大家自己看吧

C
C---- Useful integer constants 
C
      INTEGER IZERO, IONE, ITWO
      PARAMETER (IZERO=0,IONE=1,ITWO=2)
C
C---- Useful real constants 
C
      REAL ZERO,ONE,TWO,THREE,FOUR,FIVE,SIX,EIGHT,TEN,TWELVE,HUNDRED
      DOUBLE PRECISION DZERO,DONE,DTWO,DTHREE,DFOUR,DFIVE,DSIX,DEIGHT, 
     &                 DTEN,DTWELVE,DHUNDRED
      PARAMETER(ZERO=0.0D0,ONE=1.0D0,TWO=2.0D0,THREE=3.0D0,
     &          FOUR=4.0D0,FIVE=5.0D0,SIX=6.0D0,EIGHT=8.0D0,
     &          TEN=10.0D0,TWELVE=12.0D0,HUNDRED=1.0D2)
      PARAMETER(DZERO=0.0D0,DONE=1.0D0,DTWO=2.0D0,DTHREE=3.0D0,
     &          DFOUR=4.0D0,DFIVE=5.0D0,DSIX=6.0D0,DEIGHT=8.0D0,
     &          DTEN=10.0D0,DTWELVE=12.0D0,DHUNDRED=1.0D2)
C
C---- Useful real fractions
C
      REAL ONETHIRD, HALF, TWOTHIRDS, QUARTER, THREEQUARTERS
      REAL THREEHALVES
      PARAMETER (ONETHIRD = ONE/THREE, HALF = ONE/TWO)
      PARAMETER (TWOTHIRDS = TWO/THREE, QUARTER = 0.25D0)
      PARAMETER (THREEHALVES = 1.5D0, THREEQUARTERS = 0.75D0)
C
C---- Useful truncated irrationals
C
      REAL PI
      PARAMETER (PI = 3.141592654)