numpy.expand_dims(a, axis)
Expand the shape of an array.
Insert a new axis that will appear at the axis position in the expanded array shape.
Parameters:aarray_likeInput array.
axisint or tuple of intsPosition in the expanded axes where the new axis (or axes) is placed.
Deprecated since version 1.13.0: Passing an axis where axis>a.ndim will be treated as axis==a.ndim, and passing axis<-a.ndim-1 will be treated as axis==0. This behavior is deprecated.
Returns:resultndarrayView of a with the number of dimensions increased.
Examples
>>> importnumpyasnp>>> x=np.array([1,2])>>> x.shape(2,)The following is equivalent to x[np.newaxis,:] or x[np.newaxis]:
>>> y=np.expand_dims(x,axis=0)>>> yarray([[1, 2]])>>> y.shape(1, 2)The following is equivalent to x[:,np.newaxis]:
>>> y=np.expand_dims(x,axis=1)>>> yarray([[1], [2]])>>> y.shape(2, 1)axis may also be a tuple:
>>> y=np.expand_dims(x,axis=(0,1))>>> yarray([[[1, 2]]])>>> y=np.expand_dims(x,axis=(2,0))>>> yarray([[[1], [2]]])Note that some examples may use None instead of np.newaxis. These are the same objects:
>>> np.newaxisisNoneTrue