Tibshirani introduced once a more general type of Lasso, where the regularizer is $$\parallel D \alpha \parallel_1$$ instead of $\parallel \alpha \parallel_1$. [See paper](http://www.stat.cmu.edu/~ryantibs/papers/genlasso.pdf) However, there is nearly no discussion about this form and I wonder why since its a great way to deal with derivative smoothness regularizers. - Is there an easy way I overlooked to transform a general Lasso to the standard Lasso form? Thank you!