`import numpy as np` `import pandas as pd` `print(pd.__version__)` `print(np.__version__)`
``import numpy as np`
`import pandas as pd`
`arr=np.array([1,2,3]) #一维数组`
`print(arr)`
`print("arr.shape：",arr.shape) #形状`
`print("arr.ndim：",arr.ndim) #维度`
`print("arr.size：",arr.size) #大小`
`print("arr.dtype：",arr.dtype) #元素类型`
print("arr.type：",type(arr))`
2、创建一个有规则的数组
`#三个参数：起点。终点。步长` `import numpy as np` `a=np.arange(10)` `a`
