Symbolics and the creation of functions

General Usage
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1

Here is an example of code using Julia Symbolics to create a general functions -

using SymbolicUtils
using Symbolics

x = Symbolics.variable("x")
y = Symbolics.variable("y")
z = Symbolics.variable("z")

@variables F(x),G(x,y)

f = Symbolics.variable("f", T=Symbolics.FnType)(x)
g = Symbolics.variable("g", T=Symbolics.FnType)(x,y)

println(F*G)

println(f*g)

and here is the output -

G(x, y)*F(x)
ERROR: LoadError: ArgumentError: The function * cannot be applied to g(x, y) which is not a Number-like object.Define islike(::Num, ::Type{Number}) = true to enable this.
Stacktrace:
[1] assert_like(::Function, ::Type, ::Num)
@ SymbolicUtils ~/.julia/packages/SymbolicUtils/EGhOJ/src/methods.jl:43
[2] assert_like(f::Function, T::Type, a::Num, b::Num)
@ SymbolicUtils ~/.julia/packages/SymbolicUtils/EGhOJ/src/methods.jl:45
[3] *(a::Num, b::Num)
@ Symbolics ~/.julia/packages/SymbolicUtils/EGhOJ/src/methods.jl:72
[4] top-level scope
@ ~/Julia/Algebra/test1.jl:16
in expression starting at /home/brombo/Julia/Algebra/test1.jl:16

So that FG does not generate an error but fg does. I do not understand the error message. What am I supposed to do to make this work?

2

Can you open an issue? Iā€™d like to get @shashiā€™s input on this.

4

OK, I went to the Symbolics github site and created an issue.

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