The above routines can be called by FORTRAN. Their standard C counterparts have an appended _c, i.e. inifie_c, dofie_c and dmpfie_c.
For ease of use NEMO has defined counterparts where input variables can be entered by value, return valued must be obtained by reference always. In this case the names become inifien, dofien and dmpfien.
parse code for DOFIE
CODE Input Array of bytes (with trailing zero byte) or
fortran character string containing the
mathematical formula.
Maximum number of bytes is 255.
String may contain:
functions fff(..) see below for a list
of available functions
constants ccc see below
operators opr see below
parameters $n a parameter is a value
taken from a real*4
array
inserted at the position
of
$n in the expression.
1 <= n <= 32.
INIFIE Output Integer return value. A value >= 0 indicates
the number of parameters, a value < 0 indicates
that an error has occured during the parsing
of
CODE near byte number -INIFIE.
subroutine dofie(pars,n,result,errval) evaluates the expression processed by INIFIE for N parameter
sets.
does not return a useful thing, i.e. a C (void).
PARS Input Real*4 array of parameters. The parameters are
stored in the following way: The first N elements
contain parameter 1, the next N elements
parameter 2, etc. The total size of pars is
INIFIE * N.
N Input Integer*4 number of parameter sets.
(used to be Integer*2 !!!)
RESULT Output Real*4 array contains the results
ERRVAL Input Real*4 value to be put in RESULT if an error
occurred while evaluating CODE
subroutine dmpfie() dumps contents of expression stack to output
operators: The following operators are known:
+ addition - subtraction
* multiplication / division
** power
constants: The following constants are implemented:
pi 3.14159.... c speed of light (SI)
h Planck (SI) k Boltzmann (SI)
g gravitation (SI) s Stefan-Boltzman
(SI)
m mass of sun (SI) p parsec (SI)
undef errorval (see DOFIE)
Note: the Hubble constant is not included.
functions: The following mathematical functions are implemented:
abs(x) absolute value of x sqrt(x) square root of x
sin(x) sine of x asin(x) inverse sine of
x
cos(x) cosine of x acos(x) inverse cosine of
x
tan(x) tangent of x atan(x) inverse tan of x
exp(x) exponential of x sinh(x) hyperbolic sine
of x
ln(x) natural log of x cosh(x) hyperbolic cosine
of x
log(x) log (bas 10) of x tanh(x) hyperbolic tangent
of x
rad(x) convert x to radians deg(x) convert x to degrees
erf(x) error function of x erfc(x) 1-error function
max(x,y) maximum of x and y min(x,y) minimum of x and
y
sinc(x) sin(x)/x atan2(x,y) inverse tan (mod
2pi)
x = sin, y = cos
sign(x) sign of x (-1,0,1) mod(x,y) gives remainder of
x/y
int(x) truncates to integer nint(x) nearest integer
ranu(x,y) generates uniform noise between x and y
rang(x,y) generates gaussian noise with mean x and dispersion
y
ranp(x) generates poisson noise with mean x
ifeq(x,y,a,b) returns a if x equal y, else b
ifne(x,y,a,b) returns a if x not equal y, else b
ifgt(x,y,a,b) returns a if x greater y, else b
ifge(x,y,a,b) returns a if x greater or equal y, else b
iflt(x,y,a,b) returns a if x less y, else b
ifle(x,y,a,b) returns a if x less or equal y, else b
sind(x), cosd(x), tand(x) sine/cosine/tangent in degrees
Notes: The calculations are all done in double precision (double),
although the
input and output arrays are in single precision (float).
Remarks: If you cannot find your favorite constant or function in the
list,
please contact Kor Begeman. He might be persuaded to put it
in.
PROGRAM TEST
C == warning; program not conform to fortran77 and f2c interface definition
logical*1 string(255)
integer*2 inifie
integer*2 i, npar
real*4 pars(20), result(10), errval
C get wanted function from user
read(*,’(q,<n>a1)’) N,(string(k),k=1,N)
C suppose user gave: sin($1) + ln($2)
C add zero byte at the end of string
string(n+1)=0
C parse the string
npar = INIFIE( string )
C $1 indicates the first parameter, $2 the second
C npar contains the number of parameters (here 2)
C now check whether an error occurred while parsing
IF (npar .lt. 0)
THEN
write(*,*) ’ error at position’,-npar,’ in code’
STOP
CIF
C now load the parameters
FOR i = 1, 10
read(*,*) pars(i) ! load $1
CFOR
FOR i = 11, 20
read(*,*) pars(i) ! load $2
CFOR
C set error value and evaluate the function with the
C parameters stored in pars.
errval = -9999.9 ! error value
call DOFIE(pars,10,result,errval)
C The last two statements would be equivalent to the
C following statements:
C FOR i = 1,10
C p1 = pars(i) ! $1 parameters
C p2 = pars(i+10) ! $2 parameter
C IF (p2 .le. 0.0)
C THEN
C result(i) = errval ! error value
C ELSE
C result(i) = sin(p1) + log(p2) ! do the fie
C CIF
C CFOR
STOP
END
VMS Notes: If you want to use this routine in one of your programs,
an extra C library (sys$library:vaxcrtl.olb) is needed
by the linker. Gipsy programmers should use a command
file <programname>.COM, which should contain:
<programname>,lib:genlib/lib,sys$library:vaxcrtl/lib
$NEMO/src/pjt/clib fie.c (fortran callable) nemofie.c (C-callable) fie_ftoc.c
12-mar-87 document created KGB 25-mar-87 small change in document KGB 28-may-87 RJK bug removed KGB 27-oct-87 KGB bug removed RJK 15-dec-88 Minor things for INTEGER*4 unix version PJT 19-jun-89 Merged new GR version with NEMO again - routinenames appending _c PJT 26-aug-01 added cosd/sind/tand PJT