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dsp/fourier/internal/fftpack: fix formatting

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This commit is contained in:
Dan Kortschak
2022-08-05 21:49:25 +09:30
parent 5f0141ca4c
commit aedb59a6f6
6 changed files with 323 additions and 324 deletions
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66
dsp/fourier/internal/fftpack/sint.go
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@@ -14,19 +14,19 @@ import "math"
// The prime factorization of n together with a tabulation of the
// trigonometric functions are computed and stored in work.
//
// Input parameter
// Input parameter:
//
// n The length of the sequence to be transformed. The method
// is most efficient when n+1 is a product of small primes.
// n The length of the sequence to be transformed. The method
// is most efficient when n+1 is a product of small primes.
//
// Output parameter
// Output parameter:
//
// work A work array with at least ceil(2.5*n) locations.
// Different work arrays are required for different values
// of n. The contents of work must not be changed between
// calls of Sint.
// work A work array with at least ceil(2.5*n) locations.
// Different work arrays are required for different values
// of n. The contents of work must not be changed between
// calls of Sint.
//
// ifac An integer work array of length at least 15.
// ifac An integer work array of length at least 15.
func Sinti(n int, work []float64, ifac []int) {
if len(work) < 5*(n+1)/2 {
panic("fourier: short work")
@@ -54,39 +54,39 @@ func Sinti(n int, work []float64, ifac []int) {
// The array work which is used by subroutine Sint must be
// initialized by calling subroutine Sinti(n,work).
//
// Input parameters
// Input parameters:
//
// n The length of the sequence to be transformed. The method
// is most efficient when n+1 is the product of small primes.
// n The length of the sequence to be transformed. The method
// is most efficient when n+1 is the product of small primes.
//
// x An array which contains the sequence to be transformed.
// x An array which contains the sequence to be transformed.
//
//
// work A work array with dimension at least ceil(2.5*n)
// in the program that calls Sint. The work array must be
// initialized by calling subroutine Sinti(n,work) and a
// different work array must be used for each different
// value of n. This initialization does not have to be
// repeated so long as n remains unchanged thus subsequent
// transforms can be obtained faster than the first.
// work A work array with dimension at least ceil(2.5*n)
// in the program that calls Sint. The work array must be
// initialized by calling subroutine Sinti(n,work) and a
// different work array must be used for each different
// value of n. This initialization does not have to be
// repeated so long as n remains unchanged thus subsequent
// transforms can be obtained faster than the first.
//
// ifac An integer work array of length at least 15.
// ifac An integer work array of length at least 15.
//
// Output parameters
// Output parameters:
//
// x for i=1,...,n
// x(i)= the sum from k=1 to k=n
// 2*x(k)*sin(k*i*pi/(n+1))
// x for i=1,...,n
// x(i)= the sum from k=1 to k=n
// 2*x(k)*sin(k*i*pi/(n+1))
//
// A call of Sint followed by another call of
// Sint will multiply the sequence x by 2*(n+1).
// Hence Sint is the unnormalized inverse
// of itself.
// A call of Sint followed by another call of
// Sint will multiply the sequence x by 2*(n+1).
// Hence Sint is the unnormalized inverse
// of itself.
//
// work Contains initialization calculations which must not be
// destroyed between calls of Sint.
// ifac Contains initialization calculations which must not be
// destroyed between calls of Sint.
// work Contains initialization calculations which must not be
// destroyed between calls of Sint.
// ifac Contains initialization calculations which must not be
// destroyed between calls of Sint.
func Sint(n int, x, work []float64, ifac []int) {
if len(x) < n {
panic("fourier: short sequence")