Set conditions as NDArray Type

[opticodi]

Hi henon,
thanks for this great work.
I have some trouble to set conditions elementwise in NDArray type, like its needed for e.g. np.where() - function.

I hope to explain my issue right here with the following lines:

"import numpy as np

x = np.arange(-2,2,1)
a = (x != np.zeros_like(x))"

In "real" numpy I get a=[True True False True], but when I try the same in Numpy.NET I get a=True.

So my question:
How do I make Numpy.NET to test the condition element-wise?

[henon]

I lack knowledge about how to do this via the API to python. I know how we could use Expressions in C# to formulate that condition but I don't know how to convert the AST of such an expression into something that python accepts. I don't even know how numpy does this in Python, i.e. what method of np or NdArray it calls etc.

[henon]

or maybe all we need to do is clever operator overloading, maybe that is how numpy does it in Python.

[opticodi]

Hi, I appreciate for your quick answer.

Now, I found some circumvention for my issue:

I can use the numpy logic functions to get the element-wise answer.

For the example above:

"import numpy as np

x = np.arange(-2,2,1)
a = np.equal(x,np.zeros_like(x))"

gets me to a=[True True False True].

This type of expression I can also use to setup the boolean NDarray "conditions" for functions like np.where().