# How to give shape to LKJ

**URL:** <https://discourse.pymc.io/t/how-to-give-shape-to-lkj/8101>\
**Category:** Questions\
**Created:** [September 29, 2021, 2:33pm UTC](https://discourse.pymc.io/t/how-to-give-shape-to-lkj/8101 "2021-09-29T14:33:08Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Leon](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.pymc.io/leon/32/3424_2.png) [@Leon](https://discourse.pymc.io/u/Leon)\
**Post date:** [September 29, 2021, 2:33pm UTC](https://discourse.pymc.io/t/how-to-give-shape-to-lkj/8101/1 "2021-09-29T14:33:08Z")

</div>

Hey,  
I would like to build a DP with components using a LKJ-Prior. Since I know that there is no `shape`-argument for the LKJ-distribution in pymc3, I have tried to use `tt.stack` to generate my components. But I don’ t really get satisfying results…  
So I was wondering if someone has other ideas on how to bypass this problem.

So far my approach was this:

```auto
packed_L = tt.stack([pm.LKJCholeskyCov('packed_L_{}'.format(k), n=1, eta=2., 
                                        sd_dist=pm.HalfCauchy.dist(beta=2.5)) for k in range(K)])

```

Thanks in advance  
Leon