<div style="line-height:1.7;color:#000000;font-size:14px;font-family:Arial"><div> I start to learn python from ˇ¶Numpy Beginner's Guideˇ·second edition  written by Ivan Idris</div><div>now I know what the problem is ,the reason is that <span style="display: inline !important; float: none; background-color: transparent; color: rgb(0, 0, 0); font-family: Helvetica," Microsoft="" Yahei="" font-size:="" font-style:="" normal="" font-variant:="" normal="" font-weight:="" letter-spacing:="" normal="" orphans:="" text-align:="" left="" text-decoration:="" none="" text-indent:="" text-transform:="" none="" white-space:="" pre-wrap="" word-spacing:="" word-wrap:="" break-word=""> Numpy converts 2000 to an `int32`.When I use code <span style="display: inline !important; float: none; background-color: transparent; color: rgb(0, 0, 0); font-family: Helvetica," Microsoft="" Yahei="" font-size:="" font-style:="" normal="" font-variant:="" normal="" font-weight:="" letter-spacing:="" normal="" orphans:="" text-align:="" left="" text-decoration:="" none="" text-indent:="" text-transform:="" none="" white-space:="" pre-wrap="" word-spacing:="" word-wrap:="" break-word="">`a=np.arange(2000, dtype='int64')**3 that you taught me, the calculation  is correct 
thank you all  !

Yuping Wang
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