csconv.f
54 lines
| 1.3 KiB
| text/x-fortran
|
FortranFixedLexer
| r0 | C $Id: csconv.f 3304 2011-01-17 15:25:59Z brideout $ | |||
| C | ||||
| SUBROUTINE CSCONV(X,Y,Z,R,THETA,PHI,IMODE) | ||||
| C | ||||
| C jmh - 11/79 ans fortran 66 | ||||
| C | ||||
| C Converts between cartesian coordinates x,y,z and spherical | ||||
| C coordinates r,theta,phi. theta and phi are in degrees. | ||||
| C | ||||
| C Input: | ||||
| C IMODE - 1 (x,y,z) -> (r,theta,phi) | ||||
| C 2 (r,theta,phi) -> (x,y,z) | ||||
| C | ||||
| C Input, Output: | ||||
| C X, Y, Z - cartesian coordinates | ||||
| C R, THETA, PHI - spherical coordinates (degrees) | ||||
| C | ||||
| C .. Scalar Arguments .. | ||||
| DOUBLE PRECISION PHI,R,THETA,X,Y,Z | ||||
| INTEGER IMODE | ||||
| C .. | ||||
| C .. Local Scalars .. | ||||
| DOUBLE PRECISION CP,CT,DTR,P,RHO2,RLMIN,SP,ST,T | ||||
| C .. | ||||
| C .. Intrinsic Functions .. | ||||
| INTRINSIC ABS,DATAN2,DCOS,DMAX1,DSIN,DSQRT,SIGN | ||||
| C .. | ||||
| C .. Data statements .. | ||||
| DATA DTR/.0174532925199D0/ | ||||
| DATA RLMIN/1.D-38/ | ||||
| C .. | ||||
| C | ||||
| IF (IMODE.EQ.2) THEN | ||||
| C | ||||
| T = DTR*THETA | ||||
| P = DTR*PHI | ||||
| CT = DCOS(T) | ||||
| ST = DSIN(T) | ||||
| CP = DCOS(P) | ||||
| SP = DSIN(P) | ||||
| X = R*ST*CP | ||||
| Y = R*ST*SP | ||||
| Z = R*CT | ||||
| ELSE | ||||
| C | ||||
| RHO2 = X*X + Y*Y | ||||
| R = DSQRT(RHO2+Z*Z) | ||||
| THETA = DATAN2(DSQRT(RHO2),SIGN(1.D0,Z)*DMAX1(ABS(Z),RLMIN))/ | ||||
| * DTR | ||||
| PHI = DATAN2(Y,SIGN(1.D0,X)*DMAX1(ABS(X),RLMIN))/DTR | ||||
| END IF | ||||
| RETURN | ||||
| C | ||||
| END | ||||
