hfun.f
41 lines
| 1.1 KiB
| text/x-fortran
|
FortranFixedLexer
| r0 | C $Id: hfun.f 3304 2011-01-17 15:25:59Z brideout $ | |||
| C | ||||
| DOUBLE PRECISION FUNCTION HFUN(SR,EL,RANGE) | ||||
| C | ||||
| C jmh - 11/79 ans fortran 66 | ||||
| C | ||||
| C HFUN computes the height above a sphere (radius SR) of an | ||||
| C observation point at a specified elevation (EL) and range | ||||
| C (RANGE). SR and RANGE should be positive and EL should be in the | ||||
| C range 0.0 to 90.0. | ||||
| C | ||||
| C Input: | ||||
| C SR - radial distance of station from center of earth | ||||
| C EL - radar elevation | ||||
| C RANGE - range to observation point | ||||
| C | ||||
| C .. Scalar Arguments .. | ||||
| DOUBLE PRECISION EL,RANGE,SR | ||||
| C .. | ||||
| C .. Scalars in Common .. | ||||
| C .. | ||||
| C .. Local Scalars .. | ||||
| DOUBLE PRECISION DTR,SE | ||||
| C .. | ||||
| C .. Intrinsic Functions .. | ||||
| INTRINSIC DSIN,DSQRT | ||||
| C .. | ||||
| C .. Data statements .. | ||||
| DATA DTR/.0174532925199D0/ | ||||
| C .. | ||||
| C | ||||
| IF (SR.LT.1.D0 .OR. RANGE.LE.0.D0 .OR. EL.LT.0.D0 .OR. | ||||
| * EL.GT.90.D0) THEN | ||||
| HFUN = 0.D0 | ||||
| ELSE | ||||
| SE = DSIN(DTR*EL) | ||||
| HFUN = DSQRT(SR*SR+RANGE*RANGE+2.D0*SR*RANGE*SE) - SR | ||||
| END IF | ||||
| RETURN | ||||
| C | ||||
| END | ||||
