v0.8.4

SymbolicNumericIntegration v0.8.4

Closed issues:

• I want to learn this Julia calculus library (#1)
• Use @variables (#2)
• error (#3)

Merged pull requests:

• transition from @syms to @variables (#4) (@shahriariravanian)
• minor changes to testing (#5) (@shahriariravanian)
• update datadriven (#6) (@anandijain)
• try SymPy.jl (#9) (@anandijain)
• SymPy fixed in tests (#10) (@shahriariravanian)