This example shows how to perform iterative cone-beam CT reconstruction using either CPU or GPU resources. It reads its data from disk. The data can be generated by the Generate 4D data example or downloaded from Girder.
{w=200px alt="conjugate gradient 4D reconstruction"}
````{tab-item} C++
```{literalinclude} ./FourDConjugateGradient.cxx
:language: c++
```
````
````{tab-item} Python
```{literalinclude} ./FourDConjugateGradient.py
:language: python
```
````