U \Id@snddlZddlZddlmZddlmZddlmZddlm Z m Z ddl m Z ddl mZGd d d ZdS) N)_File) _pad_length) fileobj_name) BITPIX2DTYPE_BaseHDU)HDUList) PrimaryHDUc@sDeZdZdZddZddZddZdd Zed d Z d d Z dS) StreamingHDUa A class that provides the capability to stream data to a FITS file instead of requiring data to all be written at once. The following pseudocode illustrates its use:: header = astropy.io.fits.Header() for all the cards you need in the header: header[key] = (value, comment) shdu = astropy.io.fits.StreamingHDU('filename.fits', header) for each piece of data: shdu.write(data) shdu.close() cCst|tjrtd||_t|p(d}tj |}d}|r`tj |rZtj |dkrxd}nt |drx|j dkrxd}|rd|jkrttg}||dnd|jkr,|jjd d d dd |jd=d |jkr |jd}|dkrd}nt|}|jjd ddd|d d|jkr,|jjdddd d t|d|_t}|j|_||jd|_|j|_|j|_|jdkrd|_nd|_dS)a Construct a `StreamingHDU` object given a file name and a header. Parameters ---------- name : path-like or file-like The file to which the header and data will be streamed. If opened, the file object must be opened in a writeable binary mode such as 'wb' or 'ab+'. header : `Header` instance The header object associated with the data to be written to the file. Notes ----- The file will be opened and the header appended to the end of the file. If the file does not already exist, it will be created, and if the header represents a Primary header, it will be written to the beginning of the file. If the file does not exist and the provided header is not a Primary header, a default Primary HDU will be inserted at the beginning of the file and the provided header will be added as the first extension. If the file does already exist, but the provided header represents a Primary header, the header will be modified to an image extension header and appended to the end of the file. z0StreamingHDU not supported for GzipFile objects.FrTlenSIMPLE exceptionZXTENSIONZIMAGEzImage extension)afterPCOUNTNAXISznumber of parametersGCOUNTrznumber of groupsappendN) isinstancegzipGzipFile TypeErrorcopy_headerrospath expanduserexistsgetsizehasattrr rr Zwritetosetstrr_fforZ _writeheaderZ_header_offsettell _data_offsetsize_size writecomplete)selfnameheaderfilenamenewfilehdulistZdimZtmp_hdur.A/tmp/pip-unpacked-wheel-1sxf5fhv/astropy/io/fits/hdu/streaming.py__init__#sP             zStreamingHDU.__init__cCs|SNr.r(r.r.r/ __enter__szStreamingHDU.__enter__cCs |dSr1)close)r(typevalue tracebackr.r.r/__exit__szStreamingHDU.__exit__cCs|j|j}|js&||j|jkr.tdt|jd|j j krLt d|j j ddkrf| }n|}|j||j|j|jkr|jt|jdd|_|j|jS)a/ Write the given data to the stream. Parameters ---------- data : ndarray Data to stream to the file. Returns ------- writecomplete : int Flag that when `True` indicates that all of the required data has been written to the stream. Notes ----- Only the amount of data specified in the header provided to the class constructor may be written to the stream. If the provided data would cause the stream to overflow, an `OSError` exception is raised and the data is not written. Once sufficient data has been written to the stream to satisfy the amount specified in the header, the stream is padded to fill a complete FITS block and no more data will be accepted. An attempt to write more data after the stream has been filled will raise an `OSError` exception. If the dtype of the input data does not match what is expected by the header, a `TypeError` exception is raised. zCAttempt to write more data to the stream than the header specified.BITPIXz>Supplied data does not match the type specified in the header.r>T)r"r#r$r'nbytesr&OSErrorrrZdtyper)rr!ZbyteswapZ writearraywriterflush)r(datar%outputr.r.r/r>s$   zStreamingHDU.writec Csd}|jdd}|dkr|jdd}|jdd}|dkrL|dkrLd}nd}d}t||D]}||jdt|d}q^|jd}|jd d}|jd d} t||| |d }|S) zL Return the size (in bytes) of the data portion of the HDU. rrr FZGROUPSTrr9rr)rgetranger!abs) r(r%ZnaxissimpleZ random_groupsgroupsidxZbitpixZgcountZpcountr.r.r/r%s  zStreamingHDU.sizecCs|jdS)z/ Close the physical FITS file. N)r"r4r2r.r.r/r4szStreamingHDU.closeN) __name__ __module__ __qualname____doc__r0r3r8r>propertyr%r4r.r.r.r/r sc: r )rrZastropy.io.fits.filerZastropy.io.fits.headerrZastropy.io.fits.utilrbaserrr-rimager r r.r.r.r/s