[PD-cvs] SF.net SVN: pure-data: [9860] trunk/externals/mrpeach/runningmean/ runningmean.c

[mrpeach at users.sourceforge.net]

Revision: 9860
          http://pure-data.svn.sourceforge.net/pure-data/?rev=9860&view=rev
Author:   mrpeach
Date:     2008-05-20 12:53:35 -0700 (Tue, 20 May 2008)

Log Message:
-----------
Changed to using getbytes to allocate the initial array so it can be as long as you like.

Modified Paths:
--------------
    trunk/externals/mrpeach/runningmean/runningmean.c

Modified: trunk/externals/mrpeach/runningmean/runningmean.c
===================================================================
--- trunk/externals/mrpeach/runningmean/runningmean.c	2008-05-20 16:26:17 UTC (rev 9859)
+++ trunk/externals/mrpeach/runningmean/runningmean.c	2008-05-20 19:53:35 UTC (rev 9860)
@@ -2,12 +2,11 @@
 /* output the running mean of the input */
 #include "m_pd.h"
 
-/* We implement a circular buffer x_data of length x_n and */
-/* add all the values in it and divide by the */
-/* number of values to get the mean x_mean. */
+/* We implement a circular buffer x_data of length x_n */
+/* With each incoming value we sum the x_n values, then divide by */
+/* x_n to get the mean value, x_mean. */
 
-/* for simplicity and to avoid reallocation problems, we preallocate a longish array for the data */
-#define RUNNINGMEAN_MAX 1024 /* arbitrary maximum length of the data list*/
+#define RUNNINGMEAN_MAX 128 /* a default value when no valid argument is supplied */
 
 typedef struct _runningmean
 {
@@ -18,7 +17,8 @@
     t_outlet        *x_out;
     t_inlet         *x_inlet2;
     t_int           x_n;
-    t_float         x_data[RUNNINGMEAN_MAX];
+    t_int           x_originalsize;
+    t_float         *x_data;
     t_float         x_mean;
     t_int           x_pointer;
 } t_runningmean;
@@ -26,7 +26,7 @@
 static t_class *runningmean_class;
 
 void runningmean_setup(void);
-static void *runningmean_new(t_symbol *s, t_floatarg f);
+static void *runningmean_new(t_floatarg f);
 static void runningmean_free(t_runningmean *x);
 static void runningmean_bang(t_runningmean *x);
 static void runningmean_float(t_runningmean *x, t_float f);
@@ -39,12 +39,15 @@
     float   total = 0;
     int     i;
 
-    /* add a float at the current location, overwriting the oldest data */
-    x->x_data[x->x_pointer] = f;
-    if (++x->x_pointer >= x->x_n) x->x_pointer = 0; /* wrap pointer */
-    for (i = 0; i < x->x_n; ++i) total += *p++;
-    x->x_mean = total/x->x_n;
-    outlet_float(x->x_out, x->x_mean);
+    if (x->x_n > 0)
+    {
+        /* add a float at the current location, overwriting the oldest data */
+        x->x_data[x->x_pointer] = f;
+        if (++x->x_pointer >= x->x_n) x->x_pointer = 0; /* wrap pointer */
+        for (i = 0; i < x->x_n; ++i) total += *p++;
+        x->x_mean = total/x->x_n;
+        outlet_float(x->x_out, x->x_mean);
+    }
     return;
 }
 
@@ -57,12 +60,12 @@
 static void runningmean_length(t_runningmean *x, t_float f)
 {
 
-    if ((f >= 1) && ((int)f == f) && (f < RUNNINGMEAN_MAX))
+    if ((f >= 1) && ((int)f == f) && (f <= x->x_originalsize))
     {
         x->x_n = (int)f;
         runningmean_zero(x);
     }
-    else post("runningmean length must be an integer between 1 and %d.", RUNNINGMEAN_MAX);
+    else post("runningmean length must be an integer between 1 and %d.", x->x_originalsize);
     return;
 }
 
@@ -72,7 +75,7 @@
     int     i;
 
     /* zero the entire array */
-    for (i = 0; i < RUNNINGMEAN_MAX; ++i) *p++ = 0;
+    for (i = 0; i < x->x_n; ++i) *p++ = 0;
     x->x_mean = 0;
     x->x_pointer = 0;
     return;
@@ -81,26 +84,40 @@
 
 static void runningmean_free(t_runningmean *x)
 {
+    freebytes(x->x_data, x->x_originalsize);
+    x->x_originalsize = x->x_n = 0;
+    x->x_data = NULL;
     return;
 }
 
-static void *runningmean_new(t_symbol *s, t_floatarg f)
+static void *runningmean_new(t_floatarg f)
 {
     t_runningmean   *x;
 
-    post("runningmean_new %f", f);
-
     x = (t_runningmean *)pd_new(runningmean_class);
     if (x == NULL) return (x);
     x->x_out = outlet_new((t_object *)x, &s_float);
     x->x_inlet2 = inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_float, gensym("length"));
-    if (!((f >= 1) && ((int)f == f) && (f < RUNNINGMEAN_MAX)))
+    if (!((f >= 1) && ((int)f == f)))
     {
-        post("runningmean length %f must be an integer between 1 and %d, using %d", f, RUNNINGMEAN_MAX, RUNNINGMEAN_MAX);
+        post("runningmean length %0.2f must be an integer greater than 1, using %d", f, RUNNINGMEAN_MAX);
         f = RUNNINGMEAN_MAX;
     }
     {
         x->x_n = (int)f;
+        x->x_data = (t_float *)getbytes(sizeof(float)*x->x_n);
+        if (x->x_data == NULL)
+        {
+            post("runningmean unable to allocate %lu bytes of memory, using %d", sizeof(float)*x->x_n, RUNNINGMEAN_MAX);
+            x->x_n = RUNNINGMEAN_MAX;
+            //x->x_data = (t_float *)getbytes(x->x_n);
+            if (x->x_data == NULL)
+            {
+                post("runningmean unable to allocate %lu bytes of memory, using 0", x->x_n);
+                x->x_n = 0;
+            }
+        }
+        x->x_originalsize = x->x_n;
         runningmean_zero(x);
     }
     return (x);


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