moved to folders, updated etc

meanbuf/README.md

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+Averaging float buffer
+======================
+
+*(You can adjust it to use doubles, if you prefer.)*
+
+The `meanbuf_create()` function allocates a buffer.
+
+You can then call `meanbuf_add()` to add a new value into the buffer (and remove the oldest).
+This function returns the current average value.
+
+This buffer can be used for **signal smoothing** (such as from an analogue sensor).

meanbuf/meanbuf.c

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+#include <stdint.h>
+#include <malloc.h>
+
+#include "meanbuf.h"
+
+
+struct meanbuf_struct {
+	float * buf; // buffer (allocated at init)
+	size_t cap; // capacity
+	size_t nw; // next write index
+	float mean; // updated on write
+};
+
+
+/** Init a buffer */
+MeanBuf *meanbuf_create(size_t size)
+{
+	MeanBuf *mb = malloc(sizeof(MeanBuf));
+
+	if (size < 1) size = 1;
+
+	mb->buf = calloc(size, sizeof(float)); // calloc, so it starts with zeros.
+	mb->cap = size;
+	mb->nw = 0;
+	mb->mean = 0;
+
+	// clean buffer
+	for (uint16_t i = 0; i < size; i++) {
+		mb->buf[i] = 0;
+	}
+
+	return mb;
+}
+
+
+void meanbuf_destroy(MeanBuf *mb)
+{
+	if (mb == NULL) return;
+
+	if (mb->buf != NULL) {
+		free(mb->buf);
+	}
+
+	free(mb);
+}
+
+
+/** Add a value to the buffer. Returns current mean. */
+float meanbuf_add(MeanBuf *mb, float f)
+{
+	// add sample
+	mb->buf[mb->nw++] = f;
+	if (mb->nw == mb->cap) mb->nw = 0;
+
+	// calculate average
+	float acc = 0;
+	for (size_t i = 0; i < mb->cap; i++) {
+		acc += mb->buf[i];
+	}
+
+	acc /= mb->cap;
+
+	return mb->mean = acc;
+}

meanbuf/meanbuf.h

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+/**
+ * @file meanbuf.h
+ * @author Ondřej Hruška, 2016
+ *
+ * Averaging float buffer. (You can adjust it to use doubles, if you prefer.)
+ * 
+ * The meanbuf_create() function allocates a buffer.
+ * 
+ * You can then call meanbuf_add() to add a new value into the buffer (and remove the oldest).
+ * This function returns the current average value.
+ * 
+ * This buffer can be used for signal smoothing (such as from an analogue sensor).
+ *
+ * MIT license
+ */
+
+
+#pragma once
+#include <stdlib.h>
+#include <stdint.h>
+
+typedef struct meanbuf_struct MeanBuf;
+
+/** Init a buffer */
+MeanBuf *meanbuf_create(size_t size);
+
+/** Deinit a buffer (free buffer array) */
+void meanbuf_destroy(MeanBuf *mb);
+
+/** Add a value to the buffer. Returns current mean. */
+float meanbuf_add(MeanBuf *mb, float f);