Mailman 3 সেপ্টেম্বর 2015 - AstroPy

[ANN] Nestle: Nested sampling
by Kyle Barbary 11 অক্টোবর, 2015

11 অক্টোবর, 2015

Hi all, I'm pleased to announce the initial release of Nestle, a small Python package for nested sampling. ("Nestle" rhymes with "wrestle".) Nested sampling is a statistical technique for parameter estimation and model comparison, commonly used in cosmology. We've been using it in the sncosmo package and have found it to be a robust global optimizer in addition to its more typically cited benefits. Nestle implements an algorithm similar to that used in the MultiNest software, but in an open-source (MIT) licensed and easy-to-install (pure Python) package. (It was written based only on the literature, not the MultiNest source code.) In addition to this algorithm, Nestle also implements the "classic" nested sampling algorithm and the "single ellipsoid" algorithm. Nestle depends on only numpy and (optionally) scipy and supports both Python 3 and Legacy Python (formerly known as Python 2). docs: http://kbarbary.github.io/nestle source: http://github.com/kbarbary/nestle I'd appreciate any feedback on this initial release, particularly about application to real-world problems and comparisons with results from MultiNest. Thanks! - Kyle

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Apply now for the Python in Astronomy 2016 conference! (21-25th March 2016)
by Thomas Robitaille 8 অক্টোবর, 2015

8 অক্টোবর, 2015

Dear colleagues, We are very pleased to inform you that applications are now open for the Python in Astronomy 2016 conference: Python in Astronomy University of Washington eScience Institute Seattle, WA, USA 21-25th March 2016 http://python-in-astronomy.github.io/2016/ This meeting aims to bring together researchers, Python developers, users, and educators, and will include presentations, tutorials, unconference sessions, and coding sprints. In addition to sharing information about state-of-the-art Python Astronomy packages, the workshop will also focus on improving interoperability between astronomical Python packages, providing training for new contributors, and developing educational materials for Python in Astronomy. The meeting is therefore aimed not only at current developers, but also users and educators who are interested in being involved in these efforts. Note that this meeting is not intended to be a Python 'boot camp', and we do expect participants to have already at least used Python for some of their projects, even if only at a beginner level. To apply, please go to the following page: http://python-in-astronomy.github.io/2016/ and follow the link to the application form. Applications should be submitted by 9th October 2015 at the latest, and we hope to let you know by mid- to late November whether you have been accepted. Contingent on sponsorship, we hope to offer financial support for travel for a few participants. If you would like to apply for financial support, please indicate this in the last section of the application form. Please forward this email to anyone who may be interested! Best regards, The organizing committee: Kelle Cruz Perry Greenfield Eric Jeschke Mario Juric Stuart Mumford Chanda Prescod-Weinstein Thomas Robitaille Megan Sosey Erik Tollerud Jake Vanderplas

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ValueError in vstacking tables
by Brian Cherinka 5 অক্টোবর, 2015

5 অক্টোবর, 2015

Hi, I’m trying to vstack (vertically stack) two Astropy tables with different numbers of columns. The tables appear to stack correctly without error. However, upon attempting to index a row in the table, it throws me this error <repr(<astropy.table.row.Row at 0x10c72ed50>) failed: ValueError: setting an array element with a sequence.> I’m not trying to do anything fancy with mixed columns, or Quantities. Just stackin’ two good ol’ natural Tables together. One table has 84 columns, and another has 57, which are all a part of the 84 in the first table. At first glance I would guess it’s a mismatch in the dtypes of a particular column that I’m trying to merge. However, the columns all have the same dtype, format, and they are in the same order. I get no messages regarding any kind of merge errors. Any ideas on this? Thanks, Brian P.S. Full print of traceback below table3 = vstack([table1, table3],join_type=‘outer’) print table3[0] --------------------------------------------------------------------------- ValueError Traceback (most recent call last) <ipython-input-278-a0c75e8d3ef3> in <module>() ----> 1 print tmp3[0] /Users/Brian/anaconda/lib/python2.7/site-packages/astropy/table/row.pyc in __repr__(self) 176 def __repr__(self): 177 return "<{3} {0} of table\n values={1!r}\n dtype={2}>".format( --> 178 self.index, self.as_void(), self.dtype, self.__class__.__name__) 179 180 /Users/Brian/anaconda/lib/python2.7/site-packages/numpy/ma/core.pyc in __repr__(self) 5699 return self._data.__repr__() 5700 m = tuple(m) -> 5701 if not any(m): 5702 return self._data.__repr__() 5703 p = masked_print_option /Users/Brian/anaconda/lib/python2.7/site-packages/numpy/ma/core.pyc in __call__(self, a, *args, **params) 6089 method = getattr(MaskedArray, method_name, None) 6090 if method is not None: -> 6091 return method(MaskedArray(a), *args, **params) 6092 # Still here ? OK, let's call the corresponding np function 6093 method = getattr(np, method_name) /Users/Brian/anaconda/lib/python2.7/site-packages/numpy/ma/core.pyc in __new__(cls, data, mask, dtype, copy, subok, ndmin, fill_value, keep_mask, hard_mask, shrink, **options) 2649 """ 2650 # Process data............ -> 2651 _data = np.array(data, dtype=dtype, copy=copy, subok=True, ndmin=ndmin) 2652 _baseclass = getattr(data, '_baseclass', type(_data)) 2653 # Check that we're not erasing the mask.......... ValueError: setting an array element with a sequence. --------------------------------------- Brian Cherinka, Ph.D Dunlap Institute for Astronomy & Astrophysics University of Toronto Toronto, ON, Canada M5S 3H4 phone: 416-978-7299 email: cherinka(a)di.utoronto.ca ----------------------------------------

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deprecation warning from ipython
by Jonathan Slavin 2 অক্টোবর, 2015

2 অক্টোবর, 2015

Hi all, I was curious why I've started getting a deprecation warning from ipython when I import astropy: /export/slavin/python/anaconda/lib/python2.7/site-packages/IPython/kernel/__init__.py:13: ShimWarning: The `IPython.kernel` package has been deprecated. You should import from ipykernel or jupyter_client instead. "You should import from ipykernel or jupyter_client instead.", ShimWarning) It looks like it's related to the "Big Split" between ipython and jupyter. Are there plans to change the relevant part(s) of the code? Or is it an ipython issue? Regards, Jon -- ________________________________________________________ Jonathan D. Slavin Harvard-Smithsonian CfA jslavin(a)cfa.harvard.edu 60 Garden Street, MS 83 phone: (617) 496-7981 Cambridge, MA 02138-1516 cell: (781) 363-0035 USA ________________________________________________________

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Temporary files leaked by long-running process that calls astropy.utils.data.download_file
by Singer, Leo P. (GSFC-661.0)[OAK RIDGE ASSOCIATED UNIVERSITIES (ORAU)] 29 সেপ্টেম্বর, 2015

29 সেপ্টেম্বর, 2015

Hi, I have a process that is meant to run for a few days to months at a time, that is leaking temporary files whenever I download files using the functions in astropy.utils.data. I found no leaks in my own code. Then I looked in astropy.utils.data.get_readable_fileobj, and I found that the temporary files that it creates always make their way into the delete_fds list, and could not be leaked. Then I finally thought to look in astropy.utils.data.download_file itself, and found that it is leaking the files—at least until the interpreter exits cleanly! if conf.delete_temporary_downloads_at_exit: global _tempfilestodel _tempfilestodel.append(local_path) I find the astropy.utils.data module very convenient, and I would like to continue to use it in this long-running process. Would the maintainers be open to a patch that adds an option to delete these temporary files immediately, instead of at cleanup? Thanks, Leo P. Singer NASA Postdoctoral Program Fellow Goddard Space Flight Center 8800 Greenbelt Rd., B34, Room S239 Greenbelt, MD 20771

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Sine1D with phase?
by Rolf Buehler 29 সেপ্টেম্বর, 2015

29 সেপ্টেম্বর, 2015

Dear all, I would like to fit a Sine1D to a dataset, however, am I right that in the current implementation there is no phase parameter? (f(x) = A * sin(2 * pi * f * x + Phase) http://docs.astropy.org/en/stable/api/astropy.modeling.functional_models.Si… I will create a custom_model to work around this, but maybe it would be better to add a phase to the model? Thank you and all the best, Rolf -- www.rolfbuehler.net

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Mail server test
by Paul Barrett 25 সেপ্টেম্বর, 2015

25 সেপ্টেম্বর, 2015

This is just a test.

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Astroplan v0.1 Announcement
by Jazmin Berlanga Medina 11 সেপ্টেম্বর, 2015

11 সেপ্টেম্বর, 2015

Hi all! Brett Morris and Jazmin Berlanga Medina, student programmers for Astropy and the Python Sofware foundation, would like to share our Google Summer of Code project with you. We're proud to announce v0.1 of Astroplan, an observation planning and scheduling toolbox for astronomers! Astroplan is an open-source Python package and is powered by Astropy. Features include: - Calculate rise/set/transit times, alt/az positions for targets at observatories anywhere on Earth - Built-in plotting functions (airmass, parallactic angle, sky maps) - Determine which targets are "observable" given a list of constraints like moon separation, "above" some airmass, and/or within an altitude range, etc. - Built-in site list, with ability for users to add more. - Did we mention we're powered by Astropy? For more information on Astroplan, check out: http://astroplan.readthedocs.org We're just starting out and invite any astronomers, observatories, programmers and other cool people to join us in making this a great package! We're envisioning scheduling algorithms, a graphical interface and much more! Feedback and feature contribution are welcome at: https://github.com/astropy/astroplan What's Google Summer of Code? Check out: https://www.google-melange.com/gsoc/homepage/google/gsoc2015 Thanks! Jazmin Berlanga Medina & Brett Morris

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Help needed - Pix2Sky error
by Christian Johnson 10 সেপ্টেম্বর, 2015

10 সেপ্টেম্বর, 2015

Hi all, (if this is the wrong list to use for questions like this, please let me know!) I'm attempting to use astropy to get data out of a FITS file in the Aitoff projection, and was trying to use the astropy.modeling.projections.Pix2Sky_AIT class (that I found here: http://astropy.readthedocs.org/en/latest/modeling/index.html). However, when I try to use it, I get an error that there is no module of that name ("AttributeError: 'module' object has no attribute 'Pix2Sky_AIT'"). I can successfully import astropy.modeling.projections.Projection or astropy.modeling.projections.Zenithal or a few others, but most throw this error. Is there something I'm doing wrong, or does some other package need to be installed for these modules to work correctly? Thanks in advance, Christian Johnson

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Trying to read Tycho-2 catalog
by Ole Streicher 3 সেপ্টেম্বর, 2015

3 সেপ্টেম্বর, 2015

from astropy.io import ascii Hi, I am trying to read the Tycho-2 data catalog from CDS [1] with astropy.io.ascii. First question is: The catalog is split into 20 data files tyc2.dat.00 ... tyc2.dat.19[.gz]; how can I read them in? ascii.read() wants to use a single file name only, not a list of file names. When I tried to read a single file according to the help: cat = ascii.read('tyc2.dat.00', readme='ReadMe') I get a TypeError: __init__() got an unexpected keyword argument 'readme'; did I misunderstand here something or is this a (known) bug (version 1.0.3)? I then tried reader = ascii.get_reader(ascii.Cds, readme='ReadMe') cat = reader.read('tyc2.dat.00') which leads to an InconsistentTableError: Can't find table tyc2.dat.00 in ReadMe. Is there a way to specify the actual name of the catalog so that I don't have to rename the file? Finally, if I rename the file to 'tyc2.dat' (or concatenate all data files into a file of this name): cat = reader.read('tyc2.dat') I get a ValueError: Column RAmdeg failed to convert. (The column seems to contain empty values: may this be the problem?) How should I proceed here pragmatically? Or did I something completely not understand? Best regards Ole [1] http://cdsarc.u-strasbg.fr/viz-bin/Cat?I/259

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