# Cool chart grids

**URL:** <https://discourse.julialang.org/t/cool-chart-grids/37712>\
**Category:** General Usage\
**Created:** [April 16, 2020, 8:33pm UTC](https://discourse.julialang.org/t/cool-chart-grids/37712 "2020-04-16T20:33:36Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![lewis](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/lewis/32/5217_2.png) [@lewis](https://discourse.julialang.org/u/lewis)\
**Post date:** [April 16, 2020, 8:33pm UTC](https://discourse.julialang.org/t/cool-chart-grids/37712/1 "2020-04-16T20:33:36Z")

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I wanted to better understand the effects of the parameters for the gamma and Erlang distributions. I didn’t quite intuit the effects based on the formulas for the probability density function.

Carefully studying code examples for Plots, I amazingly got this to work first time, modulo font sizing on the leetle, teeny axes.

 ![image](https://global.discourse-cdn.com/julialang/original/3X/c/7/c79b0192c48436f3e89e0f9ab1ced3941318d7cf.png)  
 ![image](https://global.discourse-cdn.com/julialang/original/3X/5/8/58fcee289534a814e0cb999c351c7ec9ae357f7c.png)

I did the same thing for the Erlang distribution but trust me, it is pretty similar and the code is identical except for references to the distribution.

I was delighted when it worked.

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**Author:** ![Tamas\_Papp](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/tamas_papp/32/25949_2.png) [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Post date:** [April 17, 2020, 5:24am UTC](https://discourse.julialang.org/t/cool-chart-grids/37712/2 "2020-04-17T05:24:07Z")

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I would consider plotting the density function directly (possibly on the same scale) — the noise from random draws just makes the graph more difficult to interpret.

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**Author:** ![lewis](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/lewis/32/5217_2.png) [@lewis](https://discourse.julialang.org/u/lewis)\
**Post date:** [April 17, 2020, 3:35pm UTC](https://discourse.julialang.org/t/cool-chart-grids/37712/3 "2020-04-17T15:35:44Z")

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Random draws are the point because that is how the distributions will be used. Important to see the typical spread. I chose gamma because fractional parameters allow more control over the shape than Erlang.