GNU Octave  4.0.0 A high-level interpreted language, primarily intended for numerical computations, mostly compatible with Matlab
cuchk.f
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1  SUBROUTINE cuchk(Y, NZ, ASCLE, TOL)
2 C***BEGIN PROLOGUE CUCHK
3 C***REFER TO CSERI,CUOIK,CUNK1,CUNK2,CUNI1,CUNI2,CKSCL
4 C
5 C Y ENTERS AS A SCALED QUANTITY WHOSE MAGNITUDE IS GREATER THAN
6 C EXP(-ALIM)=ASCLE=1.0E+3*R1MACH(1)/TOL. THE TEST IS MADE TO SEE
7 C IF THE MAGNITUDE OF THE REAL OR IMAGINARY PART WOULD UNDER FLOW
8 C WHEN Y IS SCALED (BY TOL) TO ITS PROPER VALUE. Y IS ACCEPTED
9 C IF THE UNDERFLOW IS AT LEAST ONE PRECISION BELOW THE MAGNITUDE
10 C OF THE LARGEST COMPONENT; OTHERWISE THE PHASE ANGLE DOES NOT HAVE
11 C ABSOLUTE ACCURACY AND AN UNDERFLOW IS ASSUMED.
12 C
13 C***ROUTINES CALLED (NONE)
14 C***END PROLOGUE CUCHK
15 C
16  COMPLEX Y
17  REAL ASCLE, SS, ST, TOL, YR, YI
18  INTEGER NZ
19  nz = 0
20  yr = REAL(y)
21  yi = aimag(y)
22  yr = abs(yr)
23  yi = abs(yi)
24  st = amin1(yr,yi)
25  IF (st.GT.ascle) RETURN
26  ss = amax1(yr,yi)
27  st=st/tol
28  IF (ss.LT.st) nz = 1
29  RETURN
30  END
subroutine cuchk(Y, NZ, ASCLE, TOL)
Definition: cuchk.f:1
T abs(T x)
Definition: pr-output.cc:3062