老辈人算男女口诀是七七四十九算法，具体口诀是七七四十九，问娘何月有，减去生母岁，又加一十九。得数是单即为男，得数是双便是女，例如实际年龄为27岁的孕妈妈，在阴历4月怀孕，利用该公式口诀算出来的一般为单数，
I am working with a large list of points (each point has three dimensions x,y,z). I am pretty new with R, so I would like to know what is the best way to represent that kind of information.As far as
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