Esempio n. 1
0
/* DECK GAMR */
doublereal gamr_(real *x)
{
    /* System generated locals */
    real ret_val;

    /* Local variables */
    extern doublereal gamma_(real *);
    static integer irold;
    static real alngx;
    extern /* Subroutine */ int xgetf_(integer *);
    static real sgngx;
    extern /* Subroutine */ int xsetf_(integer *), algams_(real *, real *, 
	    real *), xerclr_(void);

/* ***BEGIN PROLOGUE  GAMR */
/* ***PURPOSE  Compute the reciprocal of the Gamma function. */
/* ***LIBRARY   SLATEC (FNLIB) */
/* ***CATEGORY  C7A */
/* ***TYPE      SINGLE PRECISION (GAMR-S, DGAMR-D, CGAMR-C) */
/* ***KEYWORDS  FNLIB, RECIPROCAL GAMMA FUNCTION, SPECIAL FUNCTIONS */
/* ***AUTHOR  Fullerton, W., (LANL) */
/* ***DESCRIPTION */

/* GAMR is a single precision function that evaluates the reciprocal */
/* of the gamma function for single precision argument X. */

/* ***REFERENCES  (NONE) */
/* ***ROUTINES CALLED  ALGAMS, GAMMA, XERCLR, XGETF, XSETF */
/* ***REVISION HISTORY  (YYMMDD) */
/*   770701  DATE WRITTEN */
/*   861211  REVISION DATE from Version 3.2 */
/*   891214  Prologue converted to Version 4.0 format.  (BAB) */
/*   900727  Added EXTERNAL statement.  (WRB) */
/* ***END PROLOGUE  GAMR */
/* ***FIRST EXECUTABLE STATEMENT  GAMR */
    ret_val = 0.f;
    if (*x <= 0.f && r_int(x) == *x) {
	return ret_val;
    }

    xgetf_(&irold);
    xsetf_(&c__1);
    if (dabs(*x) > 10.f) {
	goto L10;
    }
    ret_val = 1.f / gamma_(x);
    xerclr_();
    xsetf_(&irold);
    return ret_val;

L10:
    algams_(x, &alngx, &sgngx);
    xerclr_();
    xsetf_(&irold);
    ret_val = sgngx * exp(-alngx);
    return ret_val;

} /* gamr_ */
	void DynamicSlidingModeControllerTaskSpace::starting(const ros::Time& time)
	{
		// get joint positions
  		for(int i=0; i < joint_handles_.size(); i++) 
  		{
    		joint_msr_states_.q(i) = joint_handles_[i].getPosition();
    		joint_msr_states_.qdot(i) = joint_handles_[i].getVelocity();
    		joint_des_states_.q(i) = joint_msr_states_.q(i);
  			sigma_(i) = 0;

  			// coefficients > 0
  			Kd_(i) = 10;
  			gamma_(i) = 1;
  			alpha_(i) = 12;
  			lambda_(i) = 1;
  			k_(i) = 3;
    	}

    	//x_des_ = KDL::Frame(KDL::Rotation::RPY(0,0,0),KDL::Vector(-0.4,0.3,1.5));

    	cmd_flag_ = 0;
    	step_ = 0;
	}
Esempio n. 3
0
/* DECK BESYNU */
/* Subroutine */ int besynu_(real *x, real *fnu, integer *n, real *y)
{
    /* Initialized data */

    static real x1 = 3.f;
    static real x2 = 20.f;
    static real pi = 3.14159265358979f;
    static real rthpi = .797884560802865f;
    static real hpi = 1.5707963267949f;
    static real cc[8] = { .577215664901533f,-.0420026350340952f,
	    -.0421977345555443f,.007218943246663f,-2.152416741149e-4f,
	    -2.01348547807e-5f,1.133027232e-6f,6.116095e-9f };

    /* System generated locals */
    integer i__1;
    real r__1, r__2;

    /* Local variables */
    static real a[120], f, g;
    static integer i__, j, k;
    static real p, q, s, a1, a2, g1, g2, s1, s2, t1, t2, cb[120], fc, ak, bk, 
	    ck, fk, fn, rb[120];
    static integer kk;
    static real cs, sa, sb, cx;
    static integer nn;
    static real tb, fx, tm, pt, rs, ss, st, rx, cp1, cp2, cs1, cs2, rp1, rp2, 
	    rs1, rs2, cbk, cck, arg, rbk, rck, fhs, fks, cpt, dnu, fmu;
    static integer inu;
    static real tol, etx, smu, rpt, dnu2, coef, relb, flrx;
    extern doublereal gamma_(real *);
    static real etest;
    extern doublereal r1mach_(integer *);
    extern /* Subroutine */ int xermsg_(char *, char *, char *, integer *, 
	    integer *, ftnlen, ftnlen, ftnlen);

/* ***BEGIN PROLOGUE  BESYNU */
/* ***SUBSIDIARY */
/* ***PURPOSE  Subsidiary to BESY */
/* ***LIBRARY   SLATEC */
/* ***TYPE      SINGLE PRECISION (BESYNU-S, DBSYNU-D) */
/* ***AUTHOR  Amos, D. E., (SNLA) */
/* ***DESCRIPTION */

/*     Abstract */
/*         BESYNU computes N member sequences of Y Bessel functions */
/*         Y/SUB(FNU+I-1)/(X), I=1,N for non-negative orders FNU and */
/*         positive X. Equations of the references are implemented on */
/*         small orders DNU for Y/SUB(DNU)/(X) and Y/SUB(DNU+1)/(X). */
/*         Forward recursion with the three term recursion relation */
/*         generates higher orders FNU+I-1, I=1,...,N. */

/*         To start the recursion FNU is normalized to the interval */
/*         -0.5.LE.DNU.LT.0.5. A special form of the power series is */
/*         implemented on 0.LT.X.LE.X1 while the Miller algorithm for the */
/*         K Bessel function in terms of the confluent hypergeometric */
/*         function U(FNU+0.5,2*FNU+1,I*X) is implemented on X1.LT.X.LE.X */
/*         Here I is the complex number SQRT(-1.). */
/*         For X.GT.X2, the asymptotic expansion for large X is used. */
/*         When FNU is a half odd integer, a special formula for */
/*         DNU=-0.5 and DNU+1.0=0.5 is used to start the recursion. */

/*         BESYNU assumes that a significant digit SINH(X) function is */
/*         available. */

/*     Description of Arguments */

/*         Input */
/*           X      - X.GT.0.0E0 */
/*           FNU    - Order of initial Y function, FNU.GE.0.0E0 */
/*           N      - Number of members of the sequence, N.GE.1 */

/*         Output */
/*           Y      - A vector whose first N components contain values */
/*                    for the sequence Y(I)=Y/SUB(FNU+I-1), I=1,N. */

/*     Error Conditions */
/*         Improper input arguments - a fatal error */
/*         Overflow - a fatal error */

/* ***SEE ALSO  BESY */
/* ***REFERENCES  N. M. Temme, On the numerical evaluation of the ordinary */
/*                 Bessel function of the second kind, Journal of */
/*                 Computational Physics 21, (1976), pp. 343-350. */
/*               N. M. Temme, On the numerical evaluation of the modified */
/*                 Bessel function of the third kind, Journal of */
/*                 Computational Physics 19, (1975), pp. 324-337. */
/* ***ROUTINES CALLED  GAMMA, R1MACH, XERMSG */
/* ***REVISION HISTORY  (YYMMDD) */
/*   800501  DATE WRITTEN */
/*   890531  Changed all specific intrinsics to generic.  (WRB) */
/*   891214  Prologue converted to Version 4.0 format.  (BAB) */
/*   900315  CALLs to XERROR changed to CALLs to XERMSG.  (THJ) */
/*   900326  Removed duplicate information from DESCRIPTION section. */
/*           (WRB) */
/*   900328  Added TYPE section.  (WRB) */
/*   900727  Added EXTERNAL statement.  (WRB) */
/*   910408  Updated the AUTHOR and REFERENCES sections.  (WRB) */
/*   920501  Reformatted the REFERENCES section.  (WRB) */
/* ***END PROLOGUE  BESYNU */

    /* Parameter adjustments */
    --y;

    /* Function Body */
/* ***FIRST EXECUTABLE STATEMENT  BESYNU */
    ak = r1mach_(&c__3);
    tol = dmax(ak,1e-15f);
    if (*x <= 0.f) {
	goto L270;
    }
    if (*fnu < 0.f) {
	goto L280;
    }
    if (*n < 1) {
	goto L290;
    }
    rx = 2.f / *x;
    inu = (integer) (*fnu + .5f);
    dnu = *fnu - inu;
    if (dabs(dnu) == .5f) {
	goto L260;
    }
    dnu2 = 0.f;
    if (dabs(dnu) < tol) {
	goto L10;
    }
    dnu2 = dnu * dnu;
L10:
    if (*x > x1) {
	goto L120;
    }

/*     SERIES FOR X.LE.X1 */

    a1 = 1.f - dnu;
    a2 = dnu + 1.f;
    t1 = 1.f / gamma_(&a1);
    t2 = 1.f / gamma_(&a2);
    if (dabs(dnu) > .1f) {
	goto L40;
    }
/*     SERIES FOR F0 TO RESOLVE INDETERMINACY FOR SMALL ABS(DNU) */
    s = cc[0];
    ak = 1.f;
    for (k = 2; k <= 8; ++k) {
	ak *= dnu2;
	tm = cc[k - 1] * ak;
	s += tm;
	if (dabs(tm) < tol) {
	    goto L30;
	}
/* L20: */
    }
L30:
    g1 = -(s + s);
    goto L50;
L40:
    g1 = (t1 - t2) / dnu;
L50:
    g2 = t1 + t2;
    smu = 1.f;
    fc = 1.f / pi;
    flrx = log(rx);
    fmu = dnu * flrx;
    tm = 0.f;
    if (dnu == 0.f) {
	goto L60;
    }
    tm = sin(dnu * hpi) / dnu;
    tm = (dnu + dnu) * tm * tm;
    fc = dnu / sin(dnu * pi);
    if (fmu != 0.f) {
	smu = sinh(fmu) / fmu;
    }
L60:
    f = fc * (g1 * cosh(fmu) + g2 * flrx * smu);
    fx = exp(fmu);
    p = fc * t1 * fx;
    q = fc * t2 / fx;
    g = f + tm * q;
    ak = 1.f;
    ck = 1.f;
    bk = 1.f;
    s1 = g;
    s2 = p;
    if (inu > 0 || *n > 1) {
	goto L90;
    }
    if (*x < tol) {
	goto L80;
    }
    cx = *x * *x * .25f;
L70:
    f = (ak * f + p + q) / (bk - dnu2);
    p /= ak - dnu;
    q /= ak + dnu;
    g = f + tm * q;
    ck = -ck * cx / ak;
    t1 = ck * g;
    s1 += t1;
    bk = bk + ak + ak + 1.f;
    ak += 1.f;
    s = dabs(t1) / (dabs(s1) + 1.f);
    if (s > tol) {
	goto L70;
    }
L80:
    y[1] = -s1;
    return 0;
L90:
    if (*x < tol) {
	goto L110;
    }
    cx = *x * *x * .25f;
L100:
    f = (ak * f + p + q) / (bk - dnu2);
    p /= ak - dnu;
    q /= ak + dnu;
    g = f + tm * q;
    ck = -ck * cx / ak;
    t1 = ck * g;
    s1 += t1;
    t2 = ck * (p - ak * g);
    s2 += t2;
    bk = bk + ak + ak + 1.f;
    ak += 1.f;
    s = dabs(t1) / (dabs(s1) + 1.f) + dabs(t2) / (dabs(s2) + 1.f);
    if (s > tol) {
	goto L100;
    }
L110:
    s2 = -s2 * rx;
    s1 = -s1;
    goto L160;
L120:
    coef = rthpi / sqrt(*x);
    if (*x > x2) {
	goto L210;
    }

/*     MILLER ALGORITHM FOR X1.LT.X.LE.X2 */

    etest = cos(pi * dnu) / (pi * *x * tol);
    fks = 1.f;
    fhs = .25f;
    fk = 0.f;
    rck = 2.f;
    cck = *x + *x;
    rp1 = 0.f;
    cp1 = 0.f;
    rp2 = 1.f;
    cp2 = 0.f;
    k = 0;
L130:
    ++k;
    fk += 1.f;
    ak = (fhs - dnu2) / (fks + fk);
    pt = fk + 1.f;
    rbk = rck / pt;
    cbk = cck / pt;
    rpt = rp2;
    cpt = cp2;
    rp2 = rbk * rpt - cbk * cpt - ak * rp1;
    cp2 = cbk * rpt + rbk * cpt - ak * cp1;
    rp1 = rpt;
    cp1 = cpt;
    rb[k - 1] = rbk;
    cb[k - 1] = cbk;
    a[k - 1] = ak;
    rck += 2.f;
    fks = fks + fk + fk + 1.f;
    fhs = fhs + fk + fk;
/* Computing MAX */
    r__1 = dabs(rp1), r__2 = dabs(cp1);
    pt = dmax(r__1,r__2);
/* Computing 2nd power */
    r__1 = rp1 / pt;
/* Computing 2nd power */
    r__2 = cp1 / pt;
    fc = r__1 * r__1 + r__2 * r__2;
    pt = pt * sqrt(fc) * fk;
    if (etest > pt) {
	goto L130;
    }
    kk = k;
    rs = 1.f;
    cs = 0.f;
    rp1 = 0.f;
    cp1 = 0.f;
    rp2 = 1.f;
    cp2 = 0.f;
    i__1 = k;
    for (i__ = 1; i__ <= i__1; ++i__) {
	rpt = rp2;
	cpt = cp2;
	rp2 = (rb[kk - 1] * rpt - cb[kk - 1] * cpt - rp1) / a[kk - 1];
	cp2 = (cb[kk - 1] * rpt + rb[kk - 1] * cpt - cp1) / a[kk - 1];
	rp1 = rpt;
	cp1 = cpt;
	rs += rp2;
	cs += cp2;
	--kk;
/* L140: */
    }
/* Computing MAX */
    r__1 = dabs(rs), r__2 = dabs(cs);
    pt = dmax(r__1,r__2);
/* Computing 2nd power */
    r__1 = rs / pt;
/* Computing 2nd power */
    r__2 = cs / pt;
    fc = r__1 * r__1 + r__2 * r__2;
    pt *= sqrt(fc);
    rs1 = (rp2 * (rs / pt) + cp2 * (cs / pt)) / pt;
    cs1 = (cp2 * (rs / pt) - rp2 * (cs / pt)) / pt;
    fc = hpi * (dnu - .5f) - *x;
    p = cos(fc);
    q = sin(fc);
    s1 = (cs1 * q - rs1 * p) * coef;
    if (inu > 0 || *n > 1) {
	goto L150;
    }
    y[1] = s1;
    return 0;
L150:
/* Computing MAX */
    r__1 = dabs(rp2), r__2 = dabs(cp2);
    pt = dmax(r__1,r__2);
/* Computing 2nd power */
    r__1 = rp2 / pt;
/* Computing 2nd power */
    r__2 = cp2 / pt;
    fc = r__1 * r__1 + r__2 * r__2;
    pt *= sqrt(fc);
    rpt = dnu + .5f - (rp1 * (rp2 / pt) + cp1 * (cp2 / pt)) / pt;
    cpt = *x - (cp1 * (rp2 / pt) - rp1 * (cp2 / pt)) / pt;
    cs2 = cs1 * cpt - rs1 * rpt;
    rs2 = rpt * cs1 + rs1 * cpt;
    s2 = (rs2 * q + cs2 * p) * coef / *x;

/*     FORWARD RECURSION ON THE THREE TERM RECURSION RELATION */

L160:
    ck = (dnu + dnu + 2.f) / *x;
    if (*n == 1) {
	--inu;
    }
    if (inu > 0) {
	goto L170;
    }
    if (*n > 1) {
	goto L190;
    }
    s1 = s2;
    goto L190;
L170:
    i__1 = inu;
    for (i__ = 1; i__ <= i__1; ++i__) {
	st = s2;
	s2 = ck * s2 - s1;
	s1 = st;
	ck += rx;
/* L180: */
    }
    if (*n == 1) {
	s1 = s2;
    }
L190:
    y[1] = s1;
    if (*n == 1) {
	return 0;
    }
    y[2] = s2;
    if (*n == 2) {
	return 0;
    }
    i__1 = *n;
    for (i__ = 3; i__ <= i__1; ++i__) {
	y[i__] = ck * y[i__ - 1] - y[i__ - 2];
	ck += rx;
/* L200: */
    }
    return 0;

/*     ASYMPTOTIC EXPANSION FOR LARGE X, X.GT.X2 */

L210:
    nn = 2;
    if (inu == 0 && *n == 1) {
	nn = 1;
    }
    dnu2 = dnu + dnu;
    fmu = 0.f;
    if (dabs(dnu2) < tol) {
	goto L220;
    }
    fmu = dnu2 * dnu2;
L220:
    arg = *x - hpi * (dnu + .5f);
    sa = sin(arg);
    sb = cos(arg);
    etx = *x * 8.f;
    i__1 = nn;
    for (k = 1; k <= i__1; ++k) {
	s1 = s2;
	t2 = (fmu - 1.f) / etx;
	ss = t2;
	relb = tol * dabs(t2);
	t1 = etx;
	s = 1.f;
	fn = 1.f;
	ak = 0.f;
	for (j = 1; j <= 13; ++j) {
	    t1 += etx;
	    ak += 8.f;
	    fn += ak;
	    t2 = -t2 * (fmu - fn) / t1;
	    s += t2;
	    t1 += etx;
	    ak += 8.f;
	    fn += ak;
	    t2 = t2 * (fmu - fn) / t1;
	    ss += t2;
	    if (dabs(t2) <= relb) {
		goto L240;
	    }
/* L230: */
	}
L240:
	s2 = coef * (s * sa + ss * sb);
	fmu = fmu + dnu * 8.f + 4.f;
	tb = sa;
	sa = -sb;
	sb = tb;
/* L250: */
    }
    if (nn > 1) {
	goto L160;
    }
    s1 = s2;
    goto L190;

/*     FNU=HALF ODD INTEGER CASE */

L260:
    coef = rthpi / sqrt(*x);
    s1 = coef * sin(*x);
    s2 = -coef * cos(*x);
    goto L160;


L270:
    xermsg_("SLATEC", "BESYNU", "X NOT GREATER THAN ZERO", &c__2, &c__1, (
	    ftnlen)6, (ftnlen)6, (ftnlen)23);
    return 0;
L280:
    xermsg_("SLATEC", "BESYNU", "FNU NOT ZERO OR POSITIVE", &c__2, &c__1, (
	    ftnlen)6, (ftnlen)6, (ftnlen)24);
    return 0;
L290:
    xermsg_("SLATEC", "BESYNU", "N NOT GREATER THAN 0", &c__2, &c__1, (ftnlen)
	    6, (ftnlen)6, (ftnlen)20);
    return 0;
} /* besynu_ */
Esempio n. 4
0
/* DECK CHU */
doublereal chu_(real *a, real *b, real *x)
{
    /* Initialized data */

    static real pi = 3.14159265358979324f;
    static real eps = 0.f;

    /* System generated locals */
    integer i__1;
    real ret_val, r__1, r__2, r__3;
    doublereal d__1, d__2;

    /* Local variables */
    static integer i__, m, n;
    static real t, a0, b0, c0, xi, xn, xi1, sum;
    extern doublereal gamr_(real *);
    static real beps;
    extern doublereal poch_(real *, real *);
    static real alnx, pch1i;
    extern doublereal poch1_(real *, real *), r9chu_(real *, real *, real *);
    static real xeps1;
    extern doublereal gamma_(real *);
    static real aintb;
    static integer istrt;
    static real pch1ai;
    extern doublereal r1mach_(integer *);
    static real gamri1, pochai, gamrni, factor;
    extern doublereal exprel_(real *);
    extern /* Subroutine */ int xermsg_(char *, char *, char *, integer *, 
	    integer *, ftnlen, ftnlen, ftnlen);
    static real xtoeps;

/* ***BEGIN PROLOGUE  CHU */
/* ***PURPOSE  Compute the logarithmic confluent hypergeometric function. */
/* ***LIBRARY   SLATEC (FNLIB) */
/* ***CATEGORY  C11 */
/* ***TYPE      SINGLE PRECISION (CHU-S, DCHU-D) */
/* ***KEYWORDS  FNLIB, LOGARITHMIC CONFLUENT HYPERGEOMETRIC FUNCTION, */
/*             SPECIAL FUNCTIONS */
/* ***AUTHOR  Fullerton, W., (LANL) */
/* ***DESCRIPTION */

/* CHU computes the logarithmic confluent hypergeometric function, */
/* U(A,B,X). */

/* Input Parameters: */
/*       A   real */
/*       B   real */
/*       X   real and positive */

/* This routine is not valid when 1+A-B is close to zero if X is small. */

/* ***REFERENCES  (NONE) */
/* ***ROUTINES CALLED  EXPREL, GAMMA, GAMR, POCH, POCH1, R1MACH, R9CHU, */
/*                    XERMSG */
/* ***REVISION HISTORY  (YYMMDD) */
/*   770801  DATE WRITTEN */
/*   890531  Changed all specific intrinsics to generic.  (WRB) */
/*   890531  REVISION DATE from Version 3.2 */
/*   891214  Prologue converted to Version 4.0 format.  (BAB) */
/*   900315  CALLs to XERROR changed to CALLs to XERMSG.  (THJ) */
/*   900727  Added EXTERNAL statement.  (WRB) */
/* ***END PROLOGUE  CHU */
/* ***FIRST EXECUTABLE STATEMENT  CHU */
    if (eps == 0.f) {
	eps = r1mach_(&c__3);
    }

    if (*x == 0.f) {
	xermsg_("SLATEC", "CHU", "X IS ZERO SO CHU IS INFINITE", &c__1, &c__2,
		 (ftnlen)6, (ftnlen)3, (ftnlen)28);
    }
    if (*x < 0.f) {
	xermsg_("SLATEC", "CHU", "X IS NEGATIVE, USE CCHU", &c__2, &c__2, (
		ftnlen)6, (ftnlen)3, (ftnlen)23);
    }

/* Computing MAX */
    r__2 = dabs(*a);
/* Computing MAX */
    r__3 = (r__1 = *a + 1.f - *b, dabs(r__1));
    if (dmax(r__2,1.f) * dmax(r__3,1.f) < dabs(*x) * .99f) {
	goto L120;
    }

/* THE ASCENDING SERIES WILL BE USED, BECAUSE THE DESCENDING RATIONAL */
/* APPROXIMATION (WHICH IS BASED ON THE ASYMPTOTIC SERIES) IS UNSTABLE. */

    if ((r__1 = *a + 1.f - *b, dabs(r__1)) < sqrt(eps)) {
	xermsg_("SLATEC", "CHU", "ALGORITHM IS BAD WHEN 1+A-B IS NEAR ZERO F"
		"OR SMALL X", &c__10, &c__2, (ftnlen)6, (ftnlen)3, (ftnlen)52);
    }

    r__1 = *b + .5f;
    aintb = r_int(&r__1);
    if (*b < 0.f) {
	r__1 = *b - .5f;
	aintb = r_int(&r__1);
    }
    beps = *b - aintb;
    n = aintb;

    alnx = log(*x);
    xtoeps = exp(-beps * alnx);

/* EVALUATE THE FINITE SUM.     ----------------------------------------- */

    if (n >= 1) {
	goto L40;
    }

/* CONSIDER THE CASE B .LT. 1.0 FIRST. */

    sum = 1.f;
    if (n == 0) {
	goto L30;
    }

    t = 1.f;
    m = -n;
    i__1 = m;
    for (i__ = 1; i__ <= i__1; ++i__) {
	xi1 = (real) (i__ - 1);
	t = t * (*a + xi1) * *x / ((*b + xi1) * (xi1 + 1.f));
	sum += t;
/* L20: */
    }

L30:
    r__1 = *a + 1.f - *b;
    r__2 = -(*a);
    sum = poch_(&r__1, &r__2) * sum;
    goto L70;

/* NOW CONSIDER THE CASE B .GE. 1.0. */

L40:
    sum = 0.f;
    m = n - 2;
    if (m < 0) {
	goto L70;
    }
    t = 1.f;
    sum = 1.f;
    if (m == 0) {
	goto L60;
    }

    i__1 = m;
    for (i__ = 1; i__ <= i__1; ++i__) {
	xi = (real) i__;
	t = t * (*a - *b + xi) * *x / ((1.f - *b + xi) * xi);
	sum += t;
/* L50: */
    }

L60:
    r__1 = *b - 1.f;
    i__1 = 1 - n;
    sum = gamma_(&r__1) * gamr_(a) * pow_ri(x, &i__1) * xtoeps * sum;

/* NOW EVALUATE THE INFINITE SUM.     ----------------------------------- */

L70:
    istrt = 0;
    if (n < 1) {
	istrt = 1 - n;
    }
    xi = (real) istrt;

    r__1 = *a + 1.f - *b;
    factor = pow_ri(&c_b25, &n) * gamr_(&r__1) * pow_ri(x, &istrt);
    if (beps != 0.f) {
	factor = factor * beps * pi / sin(beps * pi);
    }

    pochai = poch_(a, &xi);
    r__1 = xi + 1.f;
    gamri1 = gamr_(&r__1);
    r__1 = aintb + xi;
    gamrni = gamr_(&r__1);
    r__1 = xi - beps;
    r__2 = xi + 1.f - beps;
    b0 = factor * poch_(a, &r__1) * gamrni * gamr_(&r__2);

    if ((r__1 = xtoeps - 1.f, dabs(r__1)) > .5f) {
	goto L90;
    }

/* X**(-BEPS) IS CLOSE TO 1.0, SO WE MUST BE CAREFUL IN EVALUATING */
/* THE DIFFERENCES */

    r__1 = *a + xi;
    r__2 = -beps;
    pch1ai = poch1_(&r__1, &r__2);
    r__1 = xi + 1.f - beps;
    pch1i = poch1_(&r__1, &beps);
    r__1 = *b + xi;
    r__2 = -beps;
    c0 = factor * pochai * gamrni * gamri1 * (-poch1_(&r__1, &r__2) + pch1ai 
	    - pch1i + beps * pch1ai * pch1i);

/* XEPS1 = (1.0 - X**(-BEPS)) / BEPS */
    r__1 = -beps * alnx;
    xeps1 = alnx * exprel_(&r__1);

    ret_val = sum + c0 + xeps1 * b0;
    xn = (real) n;
    for (i__ = 1; i__ <= 1000; ++i__) {
	xi = (real) (istrt + i__);
	xi1 = (real) (istrt + i__ - 1);
	b0 = (*a + xi1 - beps) * b0 * *x / ((xn + xi1) * (xi - beps));
	c0 = (*a + xi1) * c0 * *x / ((*b + xi1) * xi) - ((*a - 1.f) * (xn + 
		xi * 2.f - 1.f) + xi * (xi - beps)) * b0 / (xi * (*b + xi1) * 
		(*a + xi1 - beps));
	t = c0 + xeps1 * b0;
	ret_val += t;
	if (dabs(t) < eps * dabs(ret_val)) {
	    goto L130;
	}
/* L80: */
    }
    xermsg_("SLATEC", "CHU", "NO CONVERGENCE IN 1000 TERMS OF THE ASCENDING "
	    "SERIES", &c__3, &c__2, (ftnlen)6, (ftnlen)3, (ftnlen)52);

/* X**(-BEPS) IS VERY DIFFERENT FROM 1.0, SO THE STRAIGHTFORWARD */
/* FORMULATION IS STABLE. */

L90:
    r__1 = *b + xi;
    a0 = factor * pochai * gamr_(&r__1) * gamri1 / beps;
    b0 = xtoeps * b0 / beps;

    ret_val = sum + a0 - b0;
    for (i__ = 1; i__ <= 1000; ++i__) {
	xi = (real) (istrt + i__);
	xi1 = (real) (istrt + i__ - 1);
	a0 = (*a + xi1) * a0 * *x / ((*b + xi1) * xi);
	b0 = (*a + xi1 - beps) * b0 * *x / ((aintb + xi1) * (xi - beps));
	t = a0 - b0;
	ret_val += t;
	if (dabs(t) < eps * dabs(ret_val)) {
	    goto L130;
	}
/* L100: */
    }
    xermsg_("SLATEC", "CHU", "NO CONVERGENCE IN 1000 TERMS OF THE ASCENDING "
	    "SERIES", &c__3, &c__2, (ftnlen)6, (ftnlen)3, (ftnlen)52);

/* USE LUKE-S RATIONAL APPROX IN THE ASYMPTOTIC REGION. */

L120:
    d__1 = (doublereal) (*x);
    d__2 = (doublereal) (-(*a));
    ret_val = pow_dd(&d__1, &d__2) * r9chu_(a, b, x);

L130:
    return ret_val;
} /* chu_ */
Esempio n. 5
0
int recur(int n,int ipoly, double al, double be, double *a, double *b)
{
	/* System generated locals */
	double r__1, r__2, r__3;
	int ierr;

	/* Local variables */
	int k;
	double alpbe, t;
	double almach, be2, al2, fkm1;

/* This subroutine generates the coefficients  a(k),b(k), k=0,1,...,n-1, */
/* in the recurrence relation */

/*	   p(k+1)(x)=(x-a(k))*p(k)(x)-b(k)*p(k-1)(x), */
/*							k=0,1,...,n-1, */

/*	   p(-1)(x)=0,  p(0)(x)=1, */

/* for some classical (monic) orthogonal polynomials, and sets  b(0) */
/* equal to the total mass of the weight distribution. The results are */
/* stored in the arrays  a,b,  which hold, respectively, the coefficients */
/* a(k-1),b(k-1), k=1,2,...,n. */

/*	   Input:  n - - the number of recursion coefficients desired */
/*			   ipoly-int identifying the polynomial as follows: */
/*					 1=Legendre polynomial on (-1,1) */
/*					 2=Legendre polynomial on (0,1) */
/*					 3=Chebyshev polynomial of the first kind */
/*					 4=Chebyshev polynomial of the second kind */
/*					 5=Jacobi polynomial with parameters  al=-.5,be=.5 */
/*					 6=Jacobi polynomial with parameters  al,be */
/*					 7=generalized Laguerre polynomial with */
/*					   parameter  al */
/*					 8=Hermite polynomial */
/*			   al,be-input parameters for Jacobi and generalized */
/*					 Laguerre polynomials */

/*	   Output: a,b - arrays containing, respectively, the recursion */
/*					 coefficients  a(k-1),b(k-1), k=1,2,...,n. */
/*			   ierr -an error flag, equal to  0  on normal return, */
/*					 equal to  1  if  al  or  be  are out of range */
/*					 when  ipoly=6  or  ipoly=7, equal to  2  if  b(0) */
/*					 overflows when  ipoly=6  or  ipoly=7, equal to  3 */
/*					 if  n  is out of range, and equal to  4  if  ipoly */
/*					 is not an admissible int. In the case  ierr=2, */
/*					 the coefficient  b(0)  is set equal to the largest */
/*					 machine-representable number. */

/* The subroutine calls for the function subroutines  r1mach,gamma  and */
/* alga. The routines  gamma  and  alga, which are included in this file, */
/* evaluate respectively the gamma function and its logarithm for */
/* positive arguments. They are used only in the cases  ipoly=6  and */
/* ipoly=7. */

	/* Function Body */
	if (n < 1) {
	return(3);
	}
	almach = log(DBL_MAX);
	ierr = 0;
	for (k = 0; k < n; ++k) {
	a[k] = 0.;
	}
	
	if (ipoly == 1) {
	b[0] = 2.;
	if (n == 1) {
		return(0);
	}

	for (k = 1; k < n; ++k) {
		fkm1 = k;
		b[k] = 1. / (4. - 1. /(fkm1 * fkm1));
	}	
	return 0;
	
	} else if (ipoly == 2) {
	a[0] = .5;
	b[0] = 1.;
	if (n == 1) {
		return 0 ;
	}
	
	for (k = 1; k <= n; ++k) {
		a[k] = .5;
		fkm1 =  k;
		b[k] = .25 / (4. - 1. / (fkm1 * fkm1));
	}
	return 0;
	
	} else if (ipoly == 3) {
	b[0] = atan(1.) * 4.;
	if (n == 1) {
		return 0;
	}
	b[1] = .5;
	if (n == 2) {
		return 0;
	}
	for (k = 2; k < n; ++k) {
		b[k] = .25;
	}
	return 0;
	} else if (ipoly == 4) {
	b[0] = atan(1.) * 2.;
	if (n == 1) {
		return 0;
	}
	for (k = 1; k < n; ++k) {
		b[k] = .25;
	}
	return 0;
	} else if (ipoly == 5) {
	b[0] = atan(1.) * 4.;
	a[0] =  .5;
	if (n == 1) {
		return 0;
	}
	for (k = 1; k < n; ++k) {
		b[k] =  .25;
	}
	return 0;
	} else if (ipoly == 6) {
	if (al <=  -1. || be <=  -1.) {
		return 1;
	} else {
		alpbe = al + be;
		a[0] = (be - al) / (alpbe +  2.);
		r__1 = al +  1.;
		r__2 = be +  1.;
		r__3 = alpbe +  2.;
		t = (alpbe +  1.) * log(2.) + alga_(r__1) + alga_(
			r__2) - alga_(r__3);

		if (t > almach) {
		ierr = 2;
		b[0] = DBL_MAX;
		} else {
		b[0] = exp(t);
		}
		if (n == 1) {
		return 0;
		}
		al2 = al * al;
		be2 = be * be;
		a[1] = (be2 - al2) / ((alpbe +  2.) * (alpbe +  4.));
/* Computing 2nd power */
		r__1 = alpbe +  2.;
		b[1] = (al +  1.) *  4. * (be +  1.) / ((
			alpbe +  3.) * (r__1 * r__1));
		if (n == 2) {
		return 0;
		}
		for (k = 2; k < n; ++k) {
		fkm1 =  k;
		a[k] = (be2 - al2) *  .25 / (fkm1 * fkm1 * (alpbe * (
			float).5 / fkm1 +  1.) * ((alpbe +  2.) * 
			 .5 / fkm1 +  1.));
/* Computing 2nd power */
		r__1 = alpbe *  .5 / fkm1 +  1.;
		b[k] = (al / fkm1 +  1.) *  .25 * (be / fkm1 + (
			float)1.) * (alpbe / fkm1 +   1.) / (((alpbe + (
			float)1.) *  .5 / fkm1 +  1.) * ((alpbe - 
			 1.) *  .5 / fkm1 +  1.) * (r__1 * 
			r__1));
		}
		return 0;
	}
	} else if (ipoly == 7) {
	if (al <=  -1.) {
		return 1;
	} else {
		a[0] = al +  1.;
		r__1 = al +  1.;
		b[0] = gamma_(r__1, &ierr);
		if (ierr == 2) {
		b[0] = DBL_MAX;
		}
		if (n == 1) {
		return 0;
		}
		for (k = 0; k < n; ++k) {
		fkm1 = k;
		a[k] = fkm1 *  2. + al +  1.;
		b[k] = fkm1 * (fkm1 + al);
		}
		return 0;
	}
	} else if (ipoly == 8) {
	b[0] = sqrt(atan( 1.) *  4.);
	if (n == 1) {
		return 0;
	}
	for (k = 1; k <= n; ++k) {
		b[k] = k *  .5;
	}
	return 0;
	} else {
	ierr = 4;
	}
	return(ierr);
} /* recur_ */