[hntrader]

This is a great question and I hope you get an answer to this.

The number of woeful ad-hoc solutions I've seen to people handling matrix data in Java/C# for what should've been otherwise very basic analysis ...

Something with pandas-like capability in a lower level language would be amazing.

[krona]

Something with pandas-like capability in a lower level language would be amazing.

More like numpy than pandas but I've used x-tensor (c++) with great success in several projects: https://xtensor.readthedocs.io/en/latest/index.html

[nnm]

Every time I was forced to pandas I miss R data.frame and data.table.

[The_rationalist]

Java has faster multi dimensional array than numpy, e.g nd4j can trivially leverage Intel MKL or even offload to CUDA.

[modeless]

C# has multidimensional arrays. It's not Pandas or numpy, but it's something.