[Numpy-discussion] numpy.arcsin strange behavior?

[Poitras, D. <Dan...@nr...>]

Hello,=20
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I tried different arcsin functions on a "complex" number (z=3D0.52+0j) =
and obtained=20
the following results:=20
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cmath.asin(z) gives (0.54685095069594414+0j)   #okay=20
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-1j*log(1j*z+sqrt(1-z**2)) gives (0.54685095069594414+0j)   #okay, by =
definition=20
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numarray.arcsin(z) gives (0.54685095069594414+0j)   #still okay=20
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but=20
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numpy.arcsin(z) gives (0.54685095069594414+0.54685095069594414j)   =
#bug??=20
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Is it a bug in numpy, or is there another explanation?=20
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Thanks=20
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Daniel Poitras=20
Ottawa