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`sc, `

`x`, `s`, `c`

Returns a sine-cosine transform of the first dimension of numerical data

. `x`

may be of any positive size. In
`x`

and `s`

are returned the sine and cosine
coefficients; element `c``i`

corresponds to wavelength
`num_elem(`

. Sine transform: `x`)/i

, but
without prefactor 2 for `s`(i) = 2 *
mean(`x` * sin(#2pi * i * indgen(`x`)/num_elem(`x`)))`i = 0`

. Cosine transform:

, but without prefactor 2 for
`c`(i) = 2 * mean(`x` * cos(#2pi * i *
indgen(`x`)/num_elem(`x`)))`i = 0`

. For quickest calculation, the length of the first
dimension of

should only contain small prime factors,
like 2, 3, and 5.
`x`

The values

are always equal to zero. If the
number of elements in the first dimension is even, then
`s`(0,...)

is also equal to zero.
`s`(*-1,...)

Reverse: scb

• sc Details: |