aboutsummaryrefslogtreecommitdiff
path: root/src/pdf~.c
blob: 40a154598f659f838d04470b6ce74fde38c99471 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
/******************************************************
 *
 * zexy - implementation file
 *
 * copyleft (c) IOhannes m zmölnig
 *
 *   1999:forum::für::umläute:2004
 *
 *   institute of electronic music and acoustics (iem)
 *
 ******************************************************
 *
 * license: GNU General Public License v.2
 *
 ******************************************************/

/* get the ProbabilityDensityFunction of a signal */

#include "zexy.h"

/* ------------------------ pdf~ ----------------------------- */

static t_class *pdf_class;

typedef struct _pdf
{
  t_object x_obj;

  t_float *buf;
  int size;
  t_float halfsize;
} t_pdf;

static void clear_pdfbuf(t_pdf *x)
{
  int n = x->size;
  t_float *buf = x->buf;

  while (n--) *buf++=0.;
}

static void pdf_bang(t_pdf *x)
{
  int n = x->size;
  t_float *buf = x->buf, max = 0;
  t_atom a[2];

  while (n--) if (max < *buf++) max = buf[-1];

  n=x->size;
  buf = x->buf;

  if (max==0.) max=1.;
  max = 1./max;

  while (n--)
    {
      SETFLOAT(a, *buf++*max);
      SETFLOAT(a+1,x->size-n-1);
      outlet_list(x->x_obj.ob_outlet, &s_list, 2, (t_atom*)&a);
    }
}

static void pdf_float(t_pdf *x, t_floatarg f)
{
  if (f) pdf_bang(x); else clear_pdfbuf(x);
}

static t_int *pdf_perform(t_int *w)
{
  t_float *in = (t_float *)(w[1]);
  t_pdf *x = (t_pdf *)(w[2]);
  int n = (int)(w[3]);

  t_float *buf = x->buf;
  t_float halfsize = x->halfsize;

  while (n--)
    {
      t_float f = *in++;
      int iindex = ((f + 1.0) * halfsize)+0.5;
      buf[(iindex<0)?0:((iindex>=x->size)?x->size-1:iindex)]+=1.;
    }
  return (w+4);
}

static void pdf_dsp(t_pdf *x, t_signal **sp)
{
  x->halfsize = (x->size - 1) / 2.0;

  dsp_add(pdf_perform, 3, sp[0]->s_vec, x, sp[0]->s_n);
}

static void *pdf_new(t_floatarg f)
{
  int i = f;
  t_pdf *x = (t_pdf *)pd_new(pdf_class);
  t_float *buf;

  x->size = (i)?i:64;
  x->buf = (t_float *)getbytes(x->size * sizeof(t_float));
  buf = x->buf;
  clear_pdfbuf(x);

  outlet_new(&x->x_obj, &s_list);
    
  return (x);
}

static void pdf_free(t_pdf *x)
{
	freebytes(x->buf, x->size*sizeof(t_float));
}

static void helper(void)
{
	post("\n%c pdf~\t:: get the probability density function of a signal (-1.0 to +1.0)", HEARTSYMBOL);
	post("'bang'\t  : output a list of the probabilities of 'n' function values"
		"\n'clear'\t  : clear the buffer (set all probabilities to zero)"
		"\n<1/0>\t  : short for 'bang' and 'clear'"
		"\n'help'\t  : view this");
	post("creation :: 'pdf~ [<n>]':: get the pdf for <n> (default: 64) values");
}

void pdf_tilde_setup(void)
{
  pdf_class = class_new(gensym("pdf~"), (t_newmethod)pdf_new, (t_method)pdf_free,
			sizeof(t_pdf), 0, A_DEFFLOAT, 0);

  class_addmethod(pdf_class, nullfn, gensym("signal"), 0);
  class_addmethod(pdf_class, (t_method)pdf_dsp, gensym("dsp"), 0);

  class_addmethod(pdf_class, (t_method)pdf_bang, gensym("bang"), 0);
  class_addmethod(pdf_class, (t_method)clear_pdfbuf, gensym("clear"), 0);
  class_addfloat(pdf_class, pdf_float);

  class_addmethod(pdf_class, (t_method)helper, gensym("help"), 0);
  class_sethelpsymbol(pdf_class, gensym("zexy/pdf~"));
  zexy_register("pdf~");
}

void z_pdf__setup(void)
{
  pdf_tilde_setup();
}