[Feature request] Load stellar spectrum as dict

[pcubillos]

Hi,
The exo_dict dictionary argument of the jdi.run_pandexo(exo_dict, ...) function allows the user to pass a user-defined stellar spectrum as a filename. It would be great if the user could pass a custom stellar spectrum as a dict (removing the need to write/read to/from file).

This can be accomplish by modifying the following lines in the outTrans() function in cretate_input.py:

    if input['type'] == 'user':
        if isinstance(input['starpath'], dict):
            star = input['starpath']
        else: #if isinstance(input['starpath'], str):
            star = np.genfromtxt(input['starpath'], dtype=(float, float), names='w, f')

From the user point of view, he/she would need to set up things like this:

    exo_dict = jdi.load_exo_dict()
    # ...
    starflux = {'f':flux_array, 'w':wavelength_array}
    exo_dict['star']['type'] = 'user'
    exo_dict['star']['starpath'] = starflux
    # ...

How does this sound? If you agree, I can put a pull request.
Thanks.

[natashabatalha]

Sounds good. If you create a pull request to dev soon it'll be added to master in a week or two.