generate julia code (#21)

* inital code generation implementation

* more docs and tests

* commit missing file

* fix tests on 1.6

* add codegen for sugeno

* update documentation

* codegen of bisector defuzzifier

Author: lucaferranti

README.md

@@ -28,6 +28,8 @@ using FuzzyLogic
 - **Compatible!** Read your models from [IEC 61131-7 Fuzzy Control Language](https://ffll.sourceforge.net/fcl.htm), [IEEE 1855-2016 Fuzzy Markup Language](https://en.wikipedia.org/wiki/Fuzzy_markup_language) and Matlab Fuzzy toolbox `.fis` files.
 - **Expressive!** Clear Domain Specific Language to write your model as human readable Julia code
 - **Productive!** Several visualization tools to help debug and tune your model.
+- **Portable!** Compile your final model to Julia or C/C++ code.
+
 ## Quickstart example
 
 ```julia

docs/src/api/readwrite.md

@@ -7,6 +7,12 @@
 @sugfis
 ```
 
+## Generate Julia code
+
+```@docs
+compilefis
+```
+
 ## Read from file
 
 ```@docs

docs/src/changelog.md

@@ -8,6 +8,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - ![](https://img.shields.io/badge/new%20feature-green.svg) allow to specify input and output variables as vectors (e.g. `x[1:10]`) and support for loops to avoid repetitive code.
 - ![](https://img.shields.io/badge/new%20feature-green.svg) added support for type-2 membership functions and type-2 systems.
 - ![](https://img.shields.io/badge/new%20feature-green.svg) added parser for Fuzzy Markup Language.
+- ![](https://img.shields.io/badge/new%20feature-green.svg) added generation of native Julia code.
 
 ## v0.1.1 -- 2023-02-25
 

docs/src/index.md

@@ -28,6 +28,7 @@ using FuzzyLogic
 - **Compatible!** Read your models from [IEC 61131-7 Fuzzy Control Language](https://ffll.sourceforge.net/fcl.htm), [IEEE 1855-2016 Fuzzy Markup Language](https://en.wikipedia.org/wiki/Fuzzy_markup_language) and Matlab Fuzzy toolbox `.fis` files.
 - **Expressive!** Clear Domain Specific Language to write your model as human readable Julia code
 - **Productive!** Several visualization tools to help debug and tune your model.
+- **Portable!** Compile your final model to Julia or C/C++ code.
 
 ## Quickstart example
 

docs/src/literate/tutorials/mamdani.jl

@@ -57,7 +57,7 @@ fis = @mamfis function tipper(service, food)::tip
     service == excellent || food == delicious --> tip == generous
 
     aggregator = ProbSumAggregator
-    defuzzifier = BisectorDefuzzifier
+    defuzzifier = CentroidDefuzzifier
 end
 
 #=
@@ -186,3 +186,19 @@ res = fis(service = 2, food = 3)
 # The value of a specific output variable can be extracted using the variable name as key.
 
 res[:tip]
+
+#=
+## Code generation
+
+The model can be compiled to native Julia code using the [`compilefis`](@ref) function.
+This produces optimized Julia code independent of the library, that can be executed as
+stand-alone function.
+=#
+
+fis_ex = compilefis(fis)
+
+# The new expression can now be evaluated as normal Julia code. Notice that the generated
+# function uses positional arguments.
+
+eval(fis_ex)
+tipper(2, 3)

docs/src/literate/tutorials/sugeno.jl

@@ -75,3 +75,12 @@ Like the Mamdani case, we can plot the whole system.
 =#
 
 plot(fis)
+
+# Similarly to Mamdani, we can also generate stand-alone Julia code
+
+fis_ex = compilefis(fis)
+
+#
+
+eval(fis_ex)
+tipper(2, 3)

src/FuzzyLogic.jl

@@ -13,6 +13,7 @@ include("parser.jl")
 include("evaluation.jl")
 include("plotting.jl")
 include("genfis.jl")
+include("tojulia.jl")
 include("readwrite.jl")
 
 export DifferenceSigmoidMF, LinearMF, GeneralizedBellMF, GaussianMF, ProductSigmoidMF,
@@ -26,6 +27,7 @@ export DifferenceSigmoidMF, LinearMF, GeneralizedBellMF, GaussianMF, ProductSigm
        @mamfis, MamdaniFuzzySystem, @sugfis, SugenoFuzzySystem, set,
        LinearSugenoOutput, ConstantSugenoOutput,
        fuzzy_cmeans,
+       compilefis,
        readfis
 
 ## parsers

src/membership_functions.jl

@@ -301,8 +301,8 @@ struct PiecewiseLinearMF{T <: Real, S <: Real} <: AbstractMembershipFunction
     points::Vector{Tuple{T, S}}
 end
 function (plmf::PiecewiseLinearMF)(x::Real)
-    x <= plmf.points[1][1] && return plmf.points[1][2]
-    x >= plmf.points[end][1] && return plmf.points[end][2]
+    x <= plmf.points[1][1] && return float(plmf.points[1][2])
+    x >= plmf.points[end][1] && return float(plmf.points[end][2])
     idx = findlast(p -> x >= p[1], plmf.points)
     x1, y1 = plmf.points[idx]
     x2, y2 = plmf.points[idx + 1]