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<p class="MsoNormal">Hi Paul,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-left:.5in"><i>I'm writing a FITS package for the Julia programming language. I have a question about the output type of the image when BZERO is an integer value. The documentation implies that the output image should be a
floating point type because the BSCALE value is a float. Is this correct? If yes, then I recommend stating this explicitly in the FITS standard documentation. I also recommend suggesting the appropriate output type depending on the input type, e.g., UInt8
=> Float32, Int16 => Float32, etc.<o:p></o:p></i></p>
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<p class="MsoNormal" style="margin-left:.5in"><i><o:p> </o:p></i></p>
<p class="MsoNormal">Yes, that is the ancient implication of BSCALE. This carries over to lossy tile compression, too, which is a very fancy BSCALE operation if you look at it sideways.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Undoubtedly there are other pending tweaks to the docs. This is hard to avoid with esoteric standards, especially perhaps if they survive through multiple generations of other contingent computer technologies.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m not sure I understand your last sentence. Could you provide a table of the mappings you think should apply?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">To first order, other languages and libraries should start with the CFITSIO source for appropriate usage (or to suggest differently). One recommendation is that all FITS packages support tile compression.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Rob Seaman<o:p></o:p></p>
<p class="MsoNormal">Lunar and Planetary Laboratory<o:p></o:p></p>
<p class="MsoNormal">University of Arizona<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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