Module oc_filter_mod

1.

Purpose: definitions of the out-of-core helix filters

2.

Types

(a)

rfilter :

member type description

flt real(:) filter coefficients

lag integer(:) filter lags

(b)

cfilter :

member type description

flt complex(:) filter coefficients

lag integer(:) filter lags

3.

Functions and subroutines

(a)

subroutine allocatehelix(aa, nh)

Purpose: allocate space for the filter coefficients

• aa: helix filter (real or complex)
• nh: number of coefficients

(b)

subroutine deallocatehelix(aa)

Purpose: deallocate filter space

• aa: helix filter (real or complex)

(c)

subroutine buildfilter(ff,x_,fbox,nf,maxmem)

Purpose: build a helix filter

• ff: output filter (real or complex)
• x_: file tag for the filtering space
• fbox: multidimensional array with the filter coefficients
• nf: number of coefficients

(d)

subroutine printfilter(ff,nf)

Purpose: print the filter coefficients

• ff: filter (real or complex)
• nf: number of coefficients

B