Add files with expressions, parser, Nikuradse dataset and a new test case.

package/test/CpuInterpreterTests.jl

@@ -1,5 +1,9 @@
 using LinearAlgebra
 using BenchmarkTools
+using DelimitedFiles
+using GZip
+
+include("parser.jl") # to parse expressions from a file
 
 function test_cpu_interpreter(nrows; parallel = false)
     exprs = [
@@ -45,3 +49,27 @@ end
 @test test_cpu_interpreter(1000, parallel=true) # start julia -t 6 for six threads
 @test test_cpu_interpreter(10000)
 @test test_cpu_interpreter(10000, parallel=true)
+
+
+function test_cpu_interpreter_nikuradse() 
+    data,varnames = readdlm("data/nikuradse_1.csv", ',', header=true);
+    X = convert(Matrix{Float32}, data)
+    
+    exprs = Expr[]
+    parameters = Vector{Vector{Float32}}()
+    varnames = ["x$i" for i in 1:10]
+    paramnames = ["p$i" for i in 1:20]
+    # data/esr_nvar2_len10.txt.gz_9.txt.gz has  ~250_000 exprs
+    # data/esr_nvar2_len10.txt.gz_10.txt.gz has ~800_000 exrps
+    GZip.open("data/esr_nvar2_len10.txt.gz_9.txt.gz") do io 
+        for line in eachline(io)
+            expr, p = parse_infix(line, varnames, paramnames)
+            
+            push!(exprs, expr)
+            push!(parameters, randn(Float32, length(p)))
+        end
+    end
+    
+    
+    interpret_cpu(exprs, X, parameters) # TODO: sufficient to do up to 10 repetitions per expression, 
+end