New Plot: Violin Plot Implementation (#316)

* Resolve merge conflicts for PR, removed violin plot in this commit
This commit contains plot.jl from master

* Fix error in tests and add a test for violinplot

* Implemented Violin Plot

* Added tests for Violin plot

* Bump MCMCChains version from 7.0.0 to 7.0.1

* Run JuliaFormatter

* Added Violin Plot docs

* Add violin plot with append_chains = true examples in test and docs

* Apply suggested changes from code review

* Ran JuliaFormatter again

* Disable legends for violin plots

---------

Co-authored-by: Shravan Goswami <[email protected]>

Author: PaulinaMartin96

Project.toml

@@ -3,7 +3,7 @@ uuid = "c7f686f2-ff18-58e9-bc7b-31028e88f75d"
 keywords = ["markov chain monte carlo", "probablistic programming"]
 license = "MIT"
 desc = "Chain types and utility functions for MCMC simulations."
-version = "7.0.0"
+version = "7.0.1"
 
 [deps]
 AbstractMCMC = "80f14c24-f653-4e6a-9b94-39d6b0f70001"

docs/src/statsplots.md

@@ -83,6 +83,50 @@ histogram(chn)
 autocorplot(chn)
 ```
 
+## Violin
+
+Violin plots are similar to box plots but also show the probability density of the data at different values, smoothed by a kernel density estimator.
+
+```@example statsplots
+violinplot(chn) # Plotting parameter 1 across all chains
+```
+
+```@example statsplots
+violinplot(chn, 1) # Plotting parameter 1 across all chains
+```
+
+```@example statsplots
+violinplot(chn, :A) # Plotting a specific parameter across all chains
+```
+
+```@example statsplots
+violinplot(chn, [:C, :B, :A]) # Plotting multiple specific parameters across all chains
+```
+
+```@example statsplots
+violinplot(chn, 1, colordim = :parameter) # Plotting chain 1 across all parameters
+```
+
+```@example statsplots
+violinplot(chn, show_boxplot = false) # Plotting all parameters without the inner boxplot
+```
+
+You can also aggregate (pool) samples from all chains for a given parameter by using `append_chains = true`. This is useful when you want to visualize the overall posterior distribution without distinguishing between individual chains.
+
+```@example statsplots
+violinplot(chn, :A, append_chains = true) # Single parameter, all chains appended
+```
+
+```@example statsplots
+violinplot(chn, append_chains = true) # All parameters, all chains appended
+```
+
+You can also use the `plot` function with `seriestype = :violinplot` or `seriestype = :violin`
+
+```@example statsplots
+plot(chn, seriestype = :violin)
+```
+
 ## Corner
 
 ```@example statsplots