void combine11(vec_ptr v, data_t *dest)
{
    int i;
    int length = vec_length(v);

    *dest = IDENT;
    for (i = 0; i < length; i++) {
		data_t val;
		get_vec_element(v, i, &val);
		*dest = *dest OPER val;
    }
}

void combine12(vec_ptr v, data_t *dest)
{
    int i;
    int length = vec_length(v);
    data_t *data = get_vec_start(v);

    *dest = IDENT;
    for (i = 0; i < length; i++) {
		*dest = *dest OPER data[i];
    }
}

void combine13(vec_ptr v, data_t *dest)
{
    int i;
    int length = vec_length(v);
    data_t *data = get_vec_start(v);
    data_t x = IDENT;

    *dest = IDENT;
    for (i = 0; i < length; i++) {
		x = x OPER data[i];
    }
    *dest = x;
}

void combine14(vec_ptr v, data_t *dest)
{
    int length = vec_length(v);
    data_t *data = get_vec_start(v);
    data_t *dend = data+length;
    data_t x = IDENT;

    for (; data < dend; data++) {
		x = x OPER *data;
    }
    *dest = x;
}

void combine15(vec_ptr v, data_t *dest)
{
    int length = vec_length(v);
    int limit = length-1;
    data_t *data = get_vec_start(v);
    data_t x = IDENT;

    int i;

    /* Combine 2 elements at a time */
    for (i = 0; i < limit; i+=2) {
		x = x OPER data[i] OPER data[i+1];
    }

	/* Finish any remaining elements */
    for (; i < length; i++) {
		x = x OPER data[i];
    }
    *dest = x;
}

void combine16(vec_ptr v, data_t *dest)
{
    int length = vec_length(v);
    data_t *data = get_vec_start(v);
    int over = length%2;
    data_t *dend = data+length-over;
    data_t x = IDENT;

    while (data < dend) {
		x = x OPER data[0];
		x = x OPER data[1];
		data += 2;
    }
    dend += over;
    while (data < dend) {
		x = x OPER *data;
		data ++;
    }
    *dest = x;
}

void combine17(vec_ptr v, data_t *dest)
{
    int length = vec_length(v);
    int limit = length-1;
    data_t *data = get_vec_start(v);
    data_t x0 = IDENT;
    data_t x1 = IDENT;
    int i;

    /* Combine 2 elements at a time */
    for (i = 0; i < limit; i+=2) {
		x0 = x0 OPER data[i]; 
		x1 = x1 OPER data[i+1];
    }

    /* Finish any remaining elements */
    for (; i < length; i++) {
		x0 = x0 OPER data[i];
    }
    *dest = x0 OPER x1;
}