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<div class="">Thanks, Armando,</div>
<div class="">That is exactly the aim of the nexusformat package - to give scientists a convenient and, hopefully, reliable tool for reading and writing NeXus files that just works. Speaking as a scientist, we don’t want to worry about whether they should be
using variable-length strings or byte arrays - we just want to have variables we can manipulate in Python and store in our data files when required. We don’t want to worry about whether we have obeyed the standard, but would be delighted if the program sorted
that out for us. That is what nexusformat tries to do, and NeXpy adds other conveniences, like showing visually what items are linked in a file tree. </div>
<div class=""><br class="">
</div>
<div class="">Those who spend a lot of time developing software, on the other hand, are welcome to do their own thing. If you are happy writing your own read/write modules using, e.g., h5py, then that’s fine. But please don’t expect scientists to have to learn
h5py, then study all the NeXus rules for writing NXdata groups (not forgetting to add an ’NX_class’ attribute, a signal attribute, axes, …), and then worry about whether they should be using byte arrays or strings. </div>
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</div>
<div class="">This is a philosophical issue that I have brought up many times at NIAC meetings. The original goal of NeXus was to be a convenience tool for scientists, but it is now largely maintained by developers who are willing to read manuals. I was a little
reluctant about deprecating the NAPI for this reason, but it started to become a barrier to using the more advanced features of HDF5 and few scientists write in C anyway. Python is different - scientists will use it if we give them the right modules - I have
a student with little programming experience who writes standard-conforming NeXus files every day. My suggestion that more people use the nexusformat package, rather than just h5py, is that, as this thread shows, it is helpful to have a wide range of people
helping to debug it so that it doesn’t trip scientists up when they do use it. </div>
<div class=""><br class="">
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<div class="">With best regards,</div>
<div class="">Ray</div>
<br class="">
<div>
<blockquote type="cite" class="">
<div class="">On Jun 15, 2017, at 3:21 AM, V. Armando Solé <<a href="mailto:sole@esrf.fr" class="">sole@esrf.fr</a>> wrote:</div>
<br class="Apple-interchange-newline">
<div class="">
<div class="">Hello,<br class="">
<br class="">
On 15/06/2017 09:17, Carlos Pascual wrote:<br class="">
<blockquote type="cite" class="">And, on the other hand, if the NIAC does bless nexusformat as the preferred
<br class="">
access method for python, I think it should be stated unambiguously in the <br class="">
manual.<br class="">
</blockquote>
<br class="">
Well, at the ESRF Python programmers are using h5py.<br class="">
<br class="">
However we recommend scientists to use nexusformat as a simpler tool<br class="">
because they often work with interactive sessions.<br class="">
As you see our point of view is that nexusformat is just a convenience<br class="">
tool on top of h5py being the later the standard (Python) tool to access<br class="">
HDF5 files.<br class="">
<br class="">
What we do not recommend at all is to use the NeXus library from Python<br class="">
(or from anywhere else).<br class="">
<br class="">
The use of NAPI was unambiguously discouraged by the NIAC in past NIAC<br class="">
meetings in favour of standard tools. However I never understood why<br class="">
trainings were kept going on around an API that was considered obsolete.<br class="">
<br class="">
Best,<br class="">
<br class="">
Armando<br class="">
<br class="">
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</blockquote>
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-- <br class="">
Ray Osborn, Senior Scientist<br class="">
Materials Science Division<br class="">
Argonne National Laboratory<br class="">
Argonne, IL 60439, USA<br class="">
Phone: +1 (630) 252-9011<br class="">
Email: <a href="mailto:ROsborn@anl.gov" class="">ROsborn@anl.gov</a></div>
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