[unix-history] / man / man6 / spline.6

.th SPLINE VI 10/20/73
.sh NAME
spline \*- interpolate smooth curve
.sh SYNOPSIS
.bd spline
[ option ] ...
.sh DESCRIPTION
.it Spline
takes pairs of numbers from the standard input as abcissas and ordinates
of a function.
It produces a similar set, which
is approximately equally spaced and
includes the input set, on the standard output.
The cubic spline output
(R. W. Hamming,
.ft I
Numerical Methods for Engineers and Scientists,
.ft R
2nd ed., 349ff)
has two continuous derivatives,
and sufficiently many points to look smooth when plotted, for
example by
.it plot
(I).
.s3
The following options are recognized,
each as a separate argument.
.s3
.lp +5 5
\fBa\fR	Supply abscissas automatically (they are missing from
the input); spacing is given by the next
argument, or is assumed to be 1 if next argument is not a number.
.s3
.lp +5 5
\fBn\fR	Output approximately 
.it n
points, where
.it n
is given by the next argument.
(Default
.it n
= 100.)
.s3
.lp +5 5
\fBp\fR	Make output periodic, i.e. match
derivatives at ends.
First and last input values should normally agree.
.s3
.lp +5 5
\fBx\fR	Next 1 (or 2) arguments are lower (and upper) \fIx\fR limits.
.i0
.sh "SEE ALSO"
plot(I)
.sh AUTHOR
M. D. McIlroy
.sh BUGS
A limit of 1000 input points is enforced silently.
Commit	Line	Data
e9c01a43 DM	1	.th SPLINE VI 10/20/73
	2	.sh NAME
	3	spline \*- interpolate smooth curve
	4	.sh SYNOPSIS
	5	.bd spline
	6	[ option ] ...
	7	.sh DESCRIPTION
	8	.it Spline
	9	takes pairs of numbers from the standard input as abcissas and ordinates
	10	of a function.
	11	It produces a similar set, which
	12	is approximately equally spaced and
	13	includes the input set, on the standard output.
	14	The cubic spline output
	15	(R. W. Hamming,
	16	.ft I
	17	Numerical Methods for Engineers and Scientists,
	18	.ft R
	19	2nd ed., 349ff)
	20	has two continuous derivatives,
	21	and sufficiently many points to look smooth when plotted, for
	22	example by
	23	.it plot
	24	(I).
	25	.s3
	26	The following options are recognized,
	27	each as a separate argument.
	28	.s3
	29	.lp +5 5
	30	\fBa\fR Supply abscissas automatically (they are missing from
	31	the input); spacing is given by the next
	32	argument, or is assumed to be 1 if next argument is not a number.
	33	.s3
	34	.lp +5 5
	35	\fBn\fR Output approximately
	36	.it n
	37	points, where
	38	.it n
	39	is given by the next argument.
	40	(Default
	41	.it n
	42	= 100.)
	43	.s3
	44	.lp +5 5
	45	\fBp\fR Make output periodic, i.e. match
	46	derivatives at ends.
	47	First and last input values should normally agree.
	48	.s3
	49	.lp +5 5
	50	\fBx\fR Next 1 (or 2) arguments are lower (and upper) \fIx\fR limits.
	51	.i0
	52	.sh "SEE ALSO"
	53	plot(I)
	54	.sh AUTHOR
	55	M. D. McIlroy
	56	.sh BUGS
	57	A limit of 1000 input points is enforced silently.