moving_average_snippet.c

typedef struct {
        double average;
        size_t oldest_index;
        double *samples;
        size_t num_samples;
} movingAverage_t;

void movingAverage_update(movingAverage_t *ma, double new_sample) {
        ma->average -= ma->samples[ma->oldest_index];
        ma->samples[ma->oldest_index] = new_sample;
        ma->average += ma->samples[ma->oldest_index];
        ma->oldest_index = (ma->oldest_index + 1) % ma->num_samples;
}