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--- home_test_julia [2017/02/07 09:35]
antonello
+++ home_test_julia [2017/02/07 10:15]
antonello
@@ Line 1: / Line 1: @@
-not in code
+===== Installation =====
+**Step 1:**
+  * Option a: Get an account on [[https://juliabox.com|JuliaBox.com]] to run julia/JuMP script without installing anything on the local computer
+  * Option b: Install Julia for your platform ([[http://julialang.org/downloads/|http://julialang.org/downloads/]])
+**Step 2:**
+Run, only once, the following code to install JuMP language and a couple of open source solvers:
 <code julia>
+Pkg.update()                        # To refresh the list of newest packages
+Pkg.add("JuMP")                     # The mathematical optimisation library
+Pkg.add("GLPKMathProgInterface")    # A lineaqr and MIP solver
+Pkg.add("Ipopt")                    # A non-linear solver
+Pkg.add("DataFrames")               # A library to deal with dataframes (R-like tabular data)
+</code>
-#=
+===== Model components =====
-test
-#=
-#Transposition in JuMP of the basic transport model used in the GAMS tutorial
+==== Importing the libraries ====
-#
-#This problem finds a least cost shipping schedule that meets
-#requirements at markets and supplies at factories.
-a = ["aaa",12]
+You will need to import as a minima the ''JuMP'' module. If you wish to specify a solver engine rather than letting JuMP select a suitable one, you will need to import also the module relative to the solver, e.g. ''Ipopt'' or  ''GLPKMathProgInterface''
+<code julia>
+# Import of the JuMP and DataFrames modules (the latter one just to import the data from a header-based table, as in the original trasnport example in GAMS
+using JuMP, DataFrames
 </code>
-~~NOCACHE~~
+==== Defining the "sets" ====
+JuMP doesn't really have a concept of sets, but it uses the native containers available in the core Julia language\\Variables, parameters and constraints can be indexed using these containers.\\
+While many works with position-based lists, I find more readable using dictionaries instead. So the "sets" are represented as lists, but then everything else is a dictionary with the elements of the list as keys.\\
+One note: it seems that Julia/JuMP don't like much the "-" symbol, so I replaced it to "_".\\
+<code julia>
+## Define sets ##
+#  Sets
+#       i   canning plants   / seattle, san-diego /
+#       j   markets          / new-york, chicago, topeka / ;
+plants  = ["seattle","san_diego"]          # canning plants
+markets = ["new_york","chicago","topeka"]  # markets
+</code>