58 lines
1.8 KiB
C
58 lines
1.8 KiB
C
/*
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* Copyright © 2009 Keith Packard <keithp@keithp.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
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*/
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#include "cc.h"
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#include <stdlib.h>
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#include <math.h>
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struct cc_perioddata *
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cc_period_make(struct cc_timedata *td, double start_time, double stop_time)
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{
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int len = stop_time - start_time + 1;
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struct cc_perioddata *pd;
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int i, j;
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double t;
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pd = calloc(1, sizeof (struct cc_perioddata));
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pd->start = start_time;
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pd->step = 1;
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pd->num = len;
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pd->data = calloc(len, sizeof(double));
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j = 0;
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for (i = 0; i < pd->num; i++) {
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t = start_time + i * pd->step;
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while (j < td->num - 1 && fabs(t - td->data[j].time) >= fabs(t - td->data[j+1].time))
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j++;
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pd->data[i] = td->data[j].value;
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}
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return pd;
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}
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struct cc_perioddata *
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cc_period_low_pass(struct cc_perioddata *raw, double omega_pass, double omega_stop, double error)
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{
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struct cc_perioddata *filtered;
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filtered = calloc (1, sizeof (struct cc_perioddata));
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filtered->start = raw->start;
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filtered->step = raw->step;
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filtered->num = raw->num;
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filtered->data = cc_low_pass(raw->data, raw->num, omega_pass, omega_stop, error);
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return filtered;
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}
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