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10 Apr
2014
10 Apr
'14
10:06 p.m.
I cannot say whether the wrong placement is due to the wrong font metrics or the wrong mapping (mathop vs mathord) by ConTeXt.
I tried '\triangle T' (often used as the Laplacian operator, instead of writing it out as \nabla^2). That one comes out fine, even though \triangledown does not. But they seem to have similar kinds of defintions/mappings:
From luatex-math.tex :
\def\triangle {\Umathchar "0"0"0025B3 } \def\triangledown {\Umathchar "2"0"0025BD } So it must be a wrong font metric? -Sanjoy