Because `variant` may be thought of as "multi-type, single value", we can utilize it to implement unified interfaces for PaddlePaddle.
`DDim` plays two kinds of roles in Majel. First, it is used to indicate the size of a tensor. For example, we can construct a new `DArray` by following way:
```c++
DArrayarr=make_darray(make_ddim({2,3}),0.0f);
```
It means that `arr` will be a two-dimension tensor, or a matrix. The size of its first dimension is 2 and the second is 3. All the element value of `arr` will be initialized as 0.0 .
The second meaning of `DDim` is tensor index. For example, if we want to access the value in the 1st row and 2nd column of `arr` and set it to 1.0, we can do like this:
```c++
arr[make_ddim({0,1})]=1.0；
```
## Implement Tensor in Paddle
We want to create a Tensor class to replace Vector and Matrix, and to support high-dimensional data. The operations on Tensor are implemented in both CPU and GPU. We also want to make sure that the Tensor interface is friendly to its callers.
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@@ -142,8 +155,6 @@ You must appoint the type and dimension of a Array, whereas DArray can represent
Please reference the section of `Learn from Majel` for more details.
### ArrayView
`ViewIterator` is a class template which implements basic iterator operation, including increment(++), decrement(--), dereference(*), equalit comparisons(==) and so on.
