Improve documentation

README.md

@@ -5,7 +5,7 @@ Uses regularized evolution and simulated annealing.
 
 ## Running:
 
-You can either call the program using `eureqa` from `eureqa.py`,
+You can either call the program by calling the `eureqa` function from `eureqa.py`,
 or execute the program from the command line with, for example:
 ```bash
 python eureqa.py --threads 8 --binary-operators plus mult pow --npop 200
@@ -76,18 +76,12 @@ optional arguments:
 
 You can add more operators in `operators.jl`, or use default
 Julia ones. Make sure all operators are defined for scalar `Float32`.
-Then just call the operator in your call to `eureqa`.
+Then just specify the operator names in your call, as above.
+You can also change the dataset learned on by passing in `X` and `y` as
+numpy arrays to `eureqa(...)`.
 
-You can change the dataset in `eureqa.py` here:
-```julia
-const X = convert(Array{Float32, 2}, randn(100, 5)*2)
-# Here is the function we want to learn (x2^2 + cos(x3) - 5)
-const y = convert(Array{Float32, 1}, ((cx,)->cx^2).(X[:, 2]) + cos.(X[:, 3]) .- 5)
-```
-by either loading in a dataset, or modifying the definition of `y`.
-(The `.` are are used for vectorization of a scalar function)
-
-One can also adjust the relative probabilities of each operation here:
+One can also adjust the relative probabilities of each operation here,
+inside `eureqa.jl`:
 ```julia
 weights = [8, 1, 1, 1, 0.1, 0.5, 2]
 ```

eureqa.py

@@ -67,7 +67,7 @@ def eureqa(X=None, y=None, threads=4, parsimony=1e-3, alpha=10,
         if test == 'simple1':
             eval_str = "X[:, 2]**2 + np.cos(X[:, 3]) - 5"
         elif test == 'simple2':
-            eval_str = "X[:, 2]**3.5 + 1/abs(X[:, 0])"
+            eval_str = "np.sign(X[:, 2])*np.abs(X[:, 2])**3.5 + 1/np.abs(X[:, 0])"
 
         X = np.random.randn(100, 5)*3
         y = eval(eval_str)
@@ -151,7 +151,7 @@ if __name__ == "__main__":
             "--binary-operators", type=str, nargs="+", default=["plus", "mul"],
             help="Binary operators. Make sure they are defined in operators.jl")
     parser.add_argument(
-            "--unary-operators", type=str, default=["exp", "sin", "cos"],
+            "--unary-operators", type=str, nargs="+", default=["exp", "sin", "cos"],
             help="Unary operators. Make sure they are defined in operators.jl")
     args = vars(parser.parse_args()) #dict