Solutions for the problems on the second final dry run.

def F1(p):
    '''Number of points within unit circle'''
    d = np.sqrt(np.sum(p ** 2, axis=1))
    return np.sum(d <= 1)

def F2(p, d):
    '''Number of points with at least one neighbor within distance d.'''
    count = 0
    for i, p1 in enumerate(p):
        for j, p2 in enumerate(p):
            if i != j:
                d12 = np.sqrt(np.sum((p1 - p2) ** 2))
                if d12 <= d:
                    count += 1
                    break
    return count

def F3(rain):
    '''Largest number of consecutive days of rain.'''
    longest = 0
    current = 0
    for r in rain:
        if r > 0:
            current += 1
            if current > longest:
                longest = current
        else:
            current = 0
    return longest

def F4(table):
    '''Average rainfall for each month.'''
    result = np.zeros(12)  # you are to return an array of 12 means
    for i in range(12):
        result[i] = np.mean(table[table[:, 1] == (i + 1), 3])
    return result

def F5(rain):
    '''Number of weeks with no rain.'''
    rain.shape = (-1, 7)  # reshape into weeks
    weekly = np.sum(rain, axis=1)
    dry = weekly == 0
    dryweeks = np.sum(dry)
    return dryweeks