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-/* acosh.c
- *
- * Inverse hyperbolic cosine
- *
- *
- *
- * SYNOPSIS:
- *
- * double x, y, acosh();
- *
- * y = acosh( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns inverse hyperbolic cosine of argument.
- *
- * If 1 <= x < 1.5, a rational approximation
- *
- * sqrt(z) * P(z)/Q(z)
- *
- * where z = x-1, is used. Otherwise,
- *
- * acosh(x) = log( x + sqrt( (x-1)(x+1) ).
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC 1,3 30000 4.2e-17 1.1e-17
- * IEEE 1,3 30000 4.6e-16 8.7e-17
- *
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * acosh domain |x| < 1 NAN
- *
- */
-
-/* airy.c
- *
- * Airy function
- *
- *
- *
- * SYNOPSIS:
- *
- * double x, ai, aip, bi, bip;
- * int airy();
- *
- * airy( x, _&ai, _&aip, _&bi, _&bip );
- *
- *
- *
- * DESCRIPTION:
- *
- * Solution of the differential equation
- *
- * y"(x) = xy.
- *
- * The function returns the two independent solutions Ai, Bi
- * and their first derivatives Ai'(x), Bi'(x).
- *
- * Evaluation is by power series summation for small x,
- * by rational minimax approximations for large x.
- *
- *
- *
- * ACCURACY:
- * Error criterion is absolute when function <= 1, relative
- * when function > 1, except * denotes relative error criterion.
- * For large negative x, the absolute error increases as x^1.5.
- * For large positive x, the relative error increases as x^1.5.
- *
- * Arithmetic domain function # trials peak rms
- * IEEE -10, 0 Ai 10000 1.6e-15 2.7e-16
- * IEEE 0, 10 Ai 10000 2.3e-14* 1.8e-15*
- * IEEE -10, 0 Ai' 10000 4.6e-15 7.6e-16
- * IEEE 0, 10 Ai' 10000 1.8e-14* 1.5e-15*
- * IEEE -10, 10 Bi 30000 4.2e-15 5.3e-16
- * IEEE -10, 10 Bi' 30000 4.9e-15 7.3e-16
- * DEC -10, 0 Ai 5000 1.7e-16 2.8e-17
- * DEC 0, 10 Ai 5000 2.1e-15* 1.7e-16*
- * DEC -10, 0 Ai' 5000 4.7e-16 7.8e-17
- * DEC 0, 10 Ai' 12000 1.8e-15* 1.5e-16*
- * DEC -10, 10 Bi 10000 5.5e-16 6.8e-17
- * DEC -10, 10 Bi' 7000 5.3e-16 8.7e-17
- *
- */
-
-/* asin.c
- *
- * Inverse circular sine
- *
- *
- *
- * SYNOPSIS:
- *
- * double x, y, asin();
- *
- * y = asin( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns radian angle between -pi/2 and +pi/2 whose sine is x.
- *
- * A rational function of the form x + x**3 P(x**2)/Q(x**2)
- * is used for |x| in the interval [0, 0.5]. If |x| > 0.5 it is
- * transformed by the identity
- *
- * asin(x) = pi/2 - 2 asin( sqrt( (1-x)/2 ) ).
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -1, 1 40000 2.6e-17 7.1e-18
- * IEEE -1, 1 10^6 1.9e-16 5.4e-17
- *
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * asin domain |x| > 1 NAN
- *
- */
- /* acos()
- *
- * Inverse circular cosine
- *
- *
- *
- * SYNOPSIS:
- *
- * double x, y, acos();
- *
- * y = acos( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns radian angle between 0 and pi whose cosine
- * is x.
- *
- * Analytically, acos(x) = pi/2 - asin(x). However if |x| is
- * near 1, there is cancellation error in subtracting asin(x)
- * from pi/2. Hence if x < -0.5,
- *
- * acos(x) = pi - 2.0 * asin( sqrt((1+x)/2) );
- *
- * or if x > +0.5,
- *
- * acos(x) = 2.0 * asin( sqrt((1-x)/2) ).
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -1, 1 50000 3.3e-17 8.2e-18
- * IEEE -1, 1 10^6 2.2e-16 6.5e-17
- *
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * asin domain |x| > 1 NAN
- */
-
-/* asinh.c
- *
- * Inverse hyperbolic sine
- *
- *
- *
- * SYNOPSIS:
- *
- * double x, y, asinh();
- *
- * y = asinh( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns inverse hyperbolic sine of argument.
- *
- * If |x| < 0.5, the function is approximated by a rational
- * form x + x**3 P(x)/Q(x). Otherwise,
- *
- * asinh(x) = log( x + sqrt(1 + x*x) ).
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -3,3 75000 4.6e-17 1.1e-17
- * IEEE -1,1 30000 3.7e-16 7.8e-17
- * IEEE 1,3 30000 2.5e-16 6.7e-17
- *
- */
-
-/* atan.c
- *
- * Inverse circular tangent
- * (arctangent)
- *
- *
- *
- * SYNOPSIS:
- *
- * double x, y, atan();
- *
- * y = atan( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns radian angle between -pi/2 and +pi/2 whose tangent
- * is x.
- *
- * Range reduction is from three intervals into the interval
- * from zero to 0.66. The approximant uses a rational
- * function of degree 4/5 of the form x + x**3 P(x)/Q(x).
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -10, 10 50000 2.4e-17 8.3e-18
- * IEEE -10, 10 10^6 1.8e-16 5.0e-17
- *
- */
- /* atan2()
- *
- * Quadrant correct inverse circular tangent
- *
- *
- *
- * SYNOPSIS:
- *
- * double x, y, z, atan2();
- *
- * z = atan2( y, x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns radian angle whose tangent is y/x.
- * Define compile time symbol ANSIC = 1 for ANSI standard,
- * range -PI < z <= +PI, args (y,x); else ANSIC = 0 for range
- * 0 to 2PI, args (x,y).
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * IEEE -10, 10 10^6 2.5e-16 6.9e-17
- * See atan.c.
- *
- */
-
-/* atanh.c
- *
- * Inverse hyperbolic tangent
- *
- *
- *
- * SYNOPSIS:
- *
- * double x, y, atanh();
- *
- * y = atanh( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns inverse hyperbolic tangent of argument in the range
- * MINLOG to MAXLOG.
- *
- * If |x| < 0.5, the rational form x + x**3 P(x)/Q(x) is
- * employed. Otherwise,
- * atanh(x) = 0.5 * log( (1+x)/(1-x) ).
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -1,1 50000 2.4e-17 6.4e-18
- * IEEE -1,1 30000 1.9e-16 5.2e-17
- *
- */
-
-/* bdtr.c
- *
- * Binomial distribution
- *
- *
- *
- * SYNOPSIS:
- *
- * int k, n;
- * double p, y, bdtr();
- *
- * y = bdtr( k, n, p );
- *
- * DESCRIPTION:
- *
- * Returns the sum of the terms 0 through k of the Binomial
- * probability density:
- *
- * k
- * -- ( n ) j n-j
- * > ( ) p (1-p)
- * -- ( j )
- * j=0
- *
- * The terms are not summed directly; instead the incomplete
- * beta integral is employed, according to the formula
- *
- * y = bdtr( k, n, p ) = incbet( n-k, k+1, 1-p ).
- *
- * The arguments must be positive, with p ranging from 0 to 1.
- *
- * ACCURACY:
- *
- * Tested at random points (a,b,p), with p between 0 and 1.
- *
- * a,b Relative error:
- * arithmetic domain # trials peak rms
- * For p between 0.001 and 1:
- * IEEE 0,100 100000 4.3e-15 2.6e-16
- * See also incbet.c.
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * bdtr domain k < 0 0.0
- * n < k
- * x < 0, x > 1
- */
- /* bdtrc()
- *
- * Complemented binomial distribution
- *
- *
- *
- * SYNOPSIS:
- *
- * int k, n;
- * double p, y, bdtrc();
- *
- * y = bdtrc( k, n, p );
- *
- * DESCRIPTION:
- *
- * Returns the sum of the terms k+1 through n of the Binomial
- * probability density:
- *
- * n
- * -- ( n ) j n-j
- * > ( ) p (1-p)
- * -- ( j )
- * j=k+1
- *
- * The terms are not summed directly; instead the incomplete
- * beta integral is employed, according to the formula
- *
- * y = bdtrc( k, n, p ) = incbet( k+1, n-k, p ).
- *
- * The arguments must be positive, with p ranging from 0 to 1.
- *
- * ACCURACY:
- *
- * Tested at random points (a,b,p).
- *
- * a,b Relative error:
- * arithmetic domain # trials peak rms
- * For p between 0.001 and 1:
- * IEEE 0,100 100000 6.7e-15 8.2e-16
- * For p between 0 and .001:
- * IEEE 0,100 100000 1.5e-13 2.7e-15
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * bdtrc domain x<0, x>1, n<k 0.0
- */
- /* bdtri()
- *
- * Inverse binomial distribution
- *
- *
- *
- * SYNOPSIS:
- *
- * int k, n;
- * double p, y, bdtri();
- *
- * p = bdtr( k, n, y );
- *
- * DESCRIPTION:
- *
- * Finds the event probability p such that the sum of the
- * terms 0 through k of the Binomial probability density
- * is equal to the given cumulative probability y.
- *
- * This is accomplished using the inverse beta integral
- * function and the relation
- *
- * 1 - p = incbi( n-k, k+1, y ).
- *
- * ACCURACY:
- *
- * Tested at random points (a,b,p).
- *
- * a,b Relative error:
- * arithmetic domain # trials peak rms
- * For p between 0.001 and 1:
- * IEEE 0,100 100000 2.3e-14 6.4e-16
- * IEEE 0,10000 100000 6.6e-12 1.2e-13
- * For p between 10^-6 and 0.001:
- * IEEE 0,100 100000 2.0e-12 1.3e-14
- * IEEE 0,10000 100000 1.5e-12 3.2e-14
- * See also incbi.c.
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * bdtri domain k < 0, n <= k 0.0
- * x < 0, x > 1
- */
-
-/* beta.c
- *
- * Beta function
- *
- *
- *
- * SYNOPSIS:
- *
- * double a, b, y, beta();
- *
- * y = beta( a, b );
- *
- *
- *
- * DESCRIPTION:
- *
- * - -
- * | (a) | (b)
- * beta( a, b ) = -----------.
- * -
- * | (a+b)
- *
- * For large arguments the logarithm of the function is
- * evaluated using lgam(), then exponentiated.
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC 0,30 1700 7.7e-15 1.5e-15
- * IEEE 0,30 30000 8.1e-14 1.1e-14
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * beta overflow log(beta) > MAXLOG 0.0
- * a or b <0 integer 0.0
- *
- */
-
-/* btdtr.c
- *
- * Beta distribution
- *
- *
- *
- * SYNOPSIS:
- *
- * double a, b, x, y, btdtr();
- *
- * y = btdtr( a, b, x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns the area from zero to x under the beta density
- * function:
- *
- *
- * x
- * - -
- * | (a+b) | | a-1 b-1
- * P(x) = ---------- | t (1-t) dt
- * - - | |
- * | (a) | (b) -
- * 0
- *
- *
- * This function is identical to the incomplete beta
- * integral function incbet(a, b, x).
- *
- * The complemented function is
- *
- * 1 - P(1-x) = incbet( b, a, x );
- *
- *
- * ACCURACY:
- *
- * See incbet.c.
- *
- */
-
-/* cbrt.c
- *
- * Cube root
- *
- *
- *
- * SYNOPSIS:
- *
- * double x, y, cbrt();
- *
- * y = cbrt( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns the cube root of the argument, which may be negative.
- *
- * Range reduction involves determining the power of 2 of
- * the argument. A polynomial of degree 2 applied to the
- * mantissa, and multiplication by the cube root of 1, 2, or 4
- * approximates the root to within about 0.1%. Then Newton's
- * iteration is used three times to converge to an accurate
- * result.
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -10,10 200000 1.8e-17 6.2e-18
- * IEEE 0,1e308 30000 1.5e-16 5.0e-17
- *
- */
-
-/* chbevl.c
- *
- * Evaluate Chebyshev series
- *
- *
- *
- * SYNOPSIS:
- *
- * int N;
- * double x, y, coef[N], chebevl();
- *
- * y = chbevl( x, coef, N );
- *
- *
- *
- * DESCRIPTION:
- *
- * Evaluates the series
- *
- * N-1
- * - '
- * y = > coef[i] T (x/2)
- * - i
- * i=0
- *
- * of Chebyshev polynomials Ti at argument x/2.
- *
- * Coefficients are stored in reverse order, i.e. the zero
- * order term is last in the array. Note N is the number of
- * coefficients, not the order.
- *
- * If coefficients are for the interval a to b, x must
- * have been transformed to x -> 2(2x - b - a)/(b-a) before
- * entering the routine. This maps x from (a, b) to (-1, 1),
- * over which the Chebyshev polynomials are defined.
- *
- * If the coefficients are for the inverted interval, in
- * which (a, b) is mapped to (1/b, 1/a), the transformation
- * required is x -> 2(2ab/x - b - a)/(b-a). If b is infinity,
- * this becomes x -> 4a/x - 1.
- *
- *
- *
- * SPEED:
- *
- * Taking advantage of the recurrence properties of the
- * Chebyshev polynomials, the routine requires one more
- * addition per loop than evaluating a nested polynomial of
- * the same degree.
- *
- */
-
-/* chdtr.c
- *
- * Chi-square distribution
- *
- *
- *
- * SYNOPSIS:
- *
- * double df, x, y, chdtr();
- *
- * y = chdtr( df, x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns the area under the left hand tail (from 0 to x)
- * of the Chi square probability density function with
- * v degrees of freedom.
- *
- *
- * inf.
- * -
- * 1 | | v/2-1 -t/2
- * P( x | v ) = ----------- | t e dt
- * v/2 - | |
- * 2 | (v/2) -
- * x
- *
- * where x is the Chi-square variable.
- *
- * The incomplete gamma integral is used, according to the
- * formula
- *
- * y = chdtr( v, x ) = igam( v/2.0, x/2.0 ).
- *
- *
- * The arguments must both be positive.
- *
- *
- *
- * ACCURACY:
- *
- * See igam().
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * chdtr domain x < 0 or v < 1 0.0
- */
- /* chdtrc()
- *
- * Complemented Chi-square distribution
- *
- *
- *
- * SYNOPSIS:
- *
- * double v, x, y, chdtrc();
- *
- * y = chdtrc( v, x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns the area under the right hand tail (from x to
- * infinity) of the Chi square probability density function
- * with v degrees of freedom:
- *
- *
- * inf.
- * -
- * 1 | | v/2-1 -t/2
- * P( x | v ) = ----------- | t e dt
- * v/2 - | |
- * 2 | (v/2) -
- * x
- *
- * where x is the Chi-square variable.
- *
- * The incomplete gamma integral is used, according to the
- * formula
- *
- * y = chdtr( v, x ) = igamc( v/2.0, x/2.0 ).
- *
- *
- * The arguments must both be positive.
- *
- *
- *
- * ACCURACY:
- *
- * See igamc().
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * chdtrc domain x < 0 or v < 1 0.0
- */
- /* chdtri()
- *
- * Inverse of complemented Chi-square distribution
- *
- *
- *
- * SYNOPSIS:
- *
- * double df, x, y, chdtri();
- *
- * x = chdtri( df, y );
- *
- *
- *
- *
- * DESCRIPTION:
- *
- * Finds the Chi-square argument x such that the integral
- * from x to infinity of the Chi-square density is equal
- * to the given cumulative probability y.
- *
- * This is accomplished using the inverse gamma integral
- * function and the relation
- *
- * x/2 = igami( df/2, y );
- *
- *
- *
- *
- * ACCURACY:
- *
- * See igami.c.
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * chdtri domain y < 0 or y > 1 0.0
- * v < 1
- *
- */
-
-/* clog.c
- *
- * Complex natural logarithm
- *
- *
- *
- * SYNOPSIS:
- *
- * void clog();
- * cmplx z, w;
- *
- * clog( &z, &w );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns complex logarithm to the base e (2.718...) of
- * the complex argument x.
- *
- * If z = x + iy, r = sqrt( x**2 + y**2 ),
- * then
- * w = log(r) + i arctan(y/x).
- *
- * The arctangent ranges from -PI to +PI.
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -10,+10 7000 8.5e-17 1.9e-17
- * IEEE -10,+10 30000 5.0e-15 1.1e-16
- *
- * Larger relative error can be observed for z near 1 +i0.
- * In IEEE arithmetic the peak absolute error is 5.2e-16, rms
- * absolute error 1.0e-16.
- */
-
-/* cexp()
- *
- * Complex exponential function
- *
- *
- *
- * SYNOPSIS:
- *
- * void cexp();
- * cmplx z, w;
- *
- * cexp( &z, &w );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns the exponential of the complex argument z
- * into the complex result w.
- *
- * If
- * z = x + iy,
- * r = exp(x),
- *
- * then
- *
- * w = r cos y + i r sin y.
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -10,+10 8700 3.7e-17 1.1e-17
- * IEEE -10,+10 30000 3.0e-16 8.7e-17
- *
- */
- /* csin()
- *
- * Complex circular sine
- *
- *
- *
- * SYNOPSIS:
- *
- * void csin();
- * cmplx z, w;
- *
- * csin( &z, &w );
- *
- *
- *
- * DESCRIPTION:
- *
- * If
- * z = x + iy,
- *
- * then
- *
- * w = sin x cosh y + i cos x sinh y.
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -10,+10 8400 5.3e-17 1.3e-17
- * IEEE -10,+10 30000 3.8e-16 1.0e-16
- * Also tested by csin(casin(z)) = z.
- *
- */
- /* ccos()
- *
- * Complex circular cosine
- *
- *
- *
- * SYNOPSIS:
- *
- * void ccos();
- * cmplx z, w;
- *
- * ccos( &z, &w );
- *
- *
- *
- * DESCRIPTION:
- *
- * If
- * z = x + iy,
- *
- * then
- *
- * w = cos x cosh y - i sin x sinh y.
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -10,+10 8400 4.5e-17 1.3e-17
- * IEEE -10,+10 30000 3.8e-16 1.0e-16
- */
- /* ctan()
- *
- * Complex circular tangent
- *
- *
- *
- * SYNOPSIS:
- *
- * void ctan();
- * cmplx z, w;
- *
- * ctan( &z, &w );
- *
- *
- *
- * DESCRIPTION:
- *
- * If
- * z = x + iy,
- *
- * then
- *
- * sin 2x + i sinh 2y
- * w = --------------------.
- * cos 2x + cosh 2y
- *
- * On the real axis the denominator is zero at odd multiples
- * of PI/2. The denominator is evaluated by its Taylor
- * series near these points.
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -10,+10 5200 7.1e-17 1.6e-17
- * IEEE -10,+10 30000 7.2e-16 1.2e-16
- * Also tested by ctan * ccot = 1 and catan(ctan(z)) = z.
- */
- /* ccot()
- *
- * Complex circular cotangent
- *
- *
- *
- * SYNOPSIS:
- *
- * void ccot();
- * cmplx z, w;
- *
- * ccot( &z, &w );
- *
- *
- *
- * DESCRIPTION:
- *
- * If
- * z = x + iy,
- *
- * then
- *
- * sin 2x - i sinh 2y
- * w = --------------------.
- * cosh 2y - cos 2x
- *
- * On the real axis, the denominator has zeros at even
- * multiples of PI/2. Near these points it is evaluated
- * by a Taylor series.
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -10,+10 3000 6.5e-17 1.6e-17
- * IEEE -10,+10 30000 9.2e-16 1.2e-16
- * Also tested by ctan * ccot = 1 + i0.
- */
- /* casin()
- *
- * Complex circular arc sine
- *
- *
- *
- * SYNOPSIS:
- *
- * void casin();
- * cmplx z, w;
- *
- * casin( &z, &w );
- *
- *
- *
- * DESCRIPTION:
- *
- * Inverse complex sine:
- *
- * 2
- * w = -i clog( iz + csqrt( 1 - z ) ).
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -10,+10 10100 2.1e-15 3.4e-16
- * IEEE -10,+10 30000 2.2e-14 2.7e-15
- * Larger relative error can be observed for z near zero.
- * Also tested by csin(casin(z)) = z.
- */
-
- /* cacos()
- *
- * Complex circular arc cosine
- *
- *
- *
- * SYNOPSIS:
- *
- * void cacos();
- * cmplx z, w;
- *
- * cacos( &z, &w );
- *
- *
- *
- * DESCRIPTION:
- *
- *
- * w = arccos z = PI/2 - arcsin z.
- *
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -10,+10 5200 1.6e-15 2.8e-16
- * IEEE -10,+10 30000 1.8e-14 2.2e-15
- */
- /* catan()
- *
- * Complex circular arc tangent
- *
- *
- *
- * SYNOPSIS:
- *
- * void catan();
- * cmplx z, w;
- *
- * catan( &z, &w );
- *
- *
- *
- * DESCRIPTION:
- *
- * If
- * z = x + iy,
- *
- * then
- * 1 ( 2x )
- * Re w = - arctan(-----------) + k PI
- * 2 ( 2 2)
- * (1 - x - y )
- *
- * ( 2 2)
- * 1 (x + (y+1) )
- * Im w = - log(------------)
- * 4 ( 2 2)
- * (x + (y-1) )
- *
- * Where k is an arbitrary integer.
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -10,+10 5900 1.3e-16 7.8e-18
- * IEEE -10,+10 30000 2.3e-15 8.5e-17
- * The check catan( ctan(z) ) = z, with |x| and |y| < PI/2,
- * had peak relative error 1.5e-16, rms relative error
- * 2.9e-17. See also clog().
- */
-
-/* cmplx.c
- *
- * Complex number arithmetic
- *
- *
- *
- * SYNOPSIS:
- *
- * typedef struct {
- * double r; real part
- * double i; imaginary part
- * }cmplx;
- *
- * cmplx *a, *b, *c;
- *
- * cadd( a, b, c ); c = b + a
- * csub( a, b, c ); c = b - a
- * cmul( a, b, c ); c = b * a
- * cdiv( a, b, c ); c = b / a
- * cneg( c ); c = -c
- * cmov( b, c ); c = b
- *
- *
- *
- * DESCRIPTION:
- *
- * Addition:
- * c.r = b.r + a.r
- * c.i = b.i + a.i
- *
- * Subtraction:
- * c.r = b.r - a.r
- * c.i = b.i - a.i
- *
- * Multiplication:
- * c.r = b.r * a.r - b.i * a.i
- * c.i = b.r * a.i + b.i * a.r
- *
- * Division:
- * d = a.r * a.r + a.i * a.i
- * c.r = (b.r * a.r + b.i * a.i)/d
- * c.i = (b.i * a.r - b.r * a.i)/d
- * ACCURACY:
- *
- * In DEC arithmetic, the test (1/z) * z = 1 had peak relative
- * error 3.1e-17, rms 1.2e-17. The test (y/z) * (z/y) = 1 had
- * peak relative error 8.3e-17, rms 2.1e-17.
- *
- * Tests in the rectangle {-10,+10}:
- * Relative error:
- * arithmetic function # trials peak rms
- * DEC cadd 10000 1.4e-17 3.4e-18
- * IEEE cadd 100000 1.1e-16 2.7e-17
- * DEC csub 10000 1.4e-17 4.5e-18
- * IEEE csub 100000 1.1e-16 3.4e-17
- * DEC cmul 3000 2.3e-17 8.7e-18
- * IEEE cmul 100000 2.1e-16 6.9e-17
- * DEC cdiv 18000 4.9e-17 1.3e-17
- * IEEE cdiv 100000 3.7e-16 1.1e-16
- */
-
-/* cabs()
- *
- * Complex absolute value
- *
- *
- *
- * SYNOPSIS:
- *
- * double cabs();
- * cmplx z;
- * double a;
- *
- * a = cabs( &z );
- *
- *
- *
- * DESCRIPTION:
- *
- *
- * If z = x + iy
- *
- * then
- *
- * a = sqrt( x**2 + y**2 ).
- *
- * Overflow and underflow are avoided by testing the magnitudes
- * of x and y before squaring. If either is outside half of
- * the floating point full scale range, both are rescaled.
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -30,+30 30000 3.2e-17 9.2e-18
- * IEEE -10,+10 100000 2.7e-16 6.9e-17
- */
- /* csqrt()
- *
- * Complex square root
- *
- *
- *
- * SYNOPSIS:
- *
- * void csqrt();
- * cmplx z, w;
- *
- * csqrt( &z, &w );
- *
- *
- *
- * DESCRIPTION:
- *
- *
- * If z = x + iy, r = |z|, then
- *
- * 1/2
- * Im w = [ (r - x)/2 ] ,
- *
- * Re w = y / 2 Im w.
- *
- *
- * Note that -w is also a square root of z. The root chosen
- * is always in the upper half plane.
- *
- * Because of the potential for cancellation error in r - x,
- * the result is sharpened by doing a Heron iteration
- * (see sqrt.c) in complex arithmetic.
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC -10,+10 25000 3.2e-17 9.6e-18
- * IEEE -10,+10 100000 3.2e-16 7.7e-17
- *
- * 2
- * Also tested by csqrt( z ) = z, and tested by arguments
- * close to the real axis.
- */
-
-/* const.c
- *
- * Globally declared constants
- *
- *
- *
- * SYNOPSIS:
- *
- * extern double nameofconstant;
- *
- *
- *
- *
- * DESCRIPTION:
- *
- * This file contains a number of mathematical constants and
- * also some needed size parameters of the computer arithmetic.
- * The values are supplied as arrays of hexadecimal integers
- * for IEEE arithmetic; arrays of octal constants for DEC
- * arithmetic; and in a normal decimal scientific notation for
- * other machines. The particular notation used is determined
- * by a symbol (DEC, IBMPC, or UNK) defined in the include file
- * math.h.
- *
- * The default size parameters are as follows.
- *
- * For DEC and UNK modes:
- * MACHEP = 1.38777878078144567553E-17 2**-56
- * MAXLOG = 8.8029691931113054295988E1 log(2**127)
- * MINLOG = -8.872283911167299960540E1 log(2**-128)
- * MAXNUM = 1.701411834604692317316873e38 2**127
- *
- * For IEEE arithmetic (IBMPC):
- * MACHEP = 1.11022302462515654042E-16 2**-53
- * MAXLOG = 7.09782712893383996843E2 log(2**1024)
- * MINLOG = -7.08396418532264106224E2 log(2**-1022)
- * MAXNUM = 1.7976931348623158E308 2**1024
- *
- * The global symbols for mathematical constants are
- * PI = 3.14159265358979323846 pi
- * PIO2 = 1.57079632679489661923 pi/2
- * PIO4 = 7.85398163397448309616E-1 pi/4
- * SQRT2 = 1.41421356237309504880 sqrt(2)
- * SQRTH = 7.07106781186547524401E-1 sqrt(2)/2
- * LOG2E = 1.4426950408889634073599 1/log(2)
- * SQ2OPI = 7.9788456080286535587989E-1 sqrt( 2/pi )
- * LOGE2 = 6.93147180559945309417E-1 log(2)
- * LOGSQ2 = 3.46573590279972654709E-1 log(2)/2
- * THPIO4 = 2.35619449019234492885 3*pi/4
- * TWOOPI = 6.36619772367581343075535E-1 2/pi
- *
- * These lists are subject to change.
- */
-
-/* cosh.c
- *
- * Hyperbolic cosine
- *
- *
- *
- * SYNOPSIS:
- *
- * double x, y, cosh();
- *
- * y = cosh( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns hyperbolic cosine of argument in the range MINLOG to
- * MAXLOG.
- *
- * cosh(x) = ( exp(x) + exp(-x) )/2.
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC +- 88 50000 4.0e-17 7.7e-18
- * IEEE +-MAXLOG 30000 2.6e-16 5.7e-17
- *
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * cosh overflow |x| > MAXLOG MAXNUM
- *
- *
- */
-
-/* cpmul.c
- *
- * Multiply two polynomials with complex coefficients
- *
- *
- *
- * SYNOPSIS:
- *
- * typedef struct
- * {
- * double r;
- * double i;
- * }cmplx;
- *
- * cmplx a[], b[], c[];
- * int da, db, dc;
- *
- * cpmul( a, da, b, db, c, &dc );
- *
- *
- *
- * DESCRIPTION:
- *
- * The two argument polynomials are multiplied together, and
- * their product is placed in c.
- *
- * Each polynomial is represented by its coefficients stored
- * as an array of complex number structures (see the typedef).