relax SVN archive

svn+ssh://bugman@.../svn/relax/trunk

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r21492 | bugman | 2013-11-17 20:39:27 +0100 (Sun, 17 Nov 2013) | 5 lines

Bug fix for the lib.structure.mass.centre_of_mass() function warning when the element is not known.

This warning was buggy and resulted tracebacks.
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r21493 | bugman | 2013-11-17 20:40:51 +0100 (Sun, 17 Nov 2013) | 5 lines

Created the pipe_control.sequence.return_attached_protons() function.

This is used to return a list of proton spin containers attached to the given spin.
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r21494 | bugman | 2013-11-17 20:42:06 +0100 (Sun, 17 Nov 2013) | 3 lines

Fix for a fatal typo in the previous commit (r21493).
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