then the relevant output i get using --verbose-debug is:
matplotlib version 0.98.5.2
Using fontManager instance from /Users/perf/.matplotlib/fontList.cache
backend pdf version unknown
findfont: Matching :family=sans-serif:style=normal:variant=normal:weight=normal:stretch=normal:size=medium to Arial (/Library/Fonts/Arial.ttf) with score of 0.000000
findfont: Matching :family=STIXGeneral:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXGeneral (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXGeneral.ttf) with score of 0.000000
findfont: Matching :family=STIXNonUnicode:style=normal:variant=normal:weight=bold:stretch=normal:size=12.0 to STIXNonUnicode (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXNonUniBol.ttf) with score of 0.000000
findfont: Matching :family=STIXGeneral:style=normal:variant=normal:weight=bold:stretch=normal:size=12.0 to STIXGeneral (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXGeneralBol.ttf) with score of 0.000000
findfont: Matching :family=STIXSize3:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXSize3 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXSiz3Sym.ttf) with score of 0.000000
findfont: Matching :family=STIXSize4:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXSize4 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXSiz4Sym.ttf) with score of 0.000000
findfont: Matching :family=STIXSize5:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXSize5 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXSiz5Sym.ttf) with score of 0.000000
findfont: Matching :family=STIXSize1:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXSize1 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXSiz1Sym.ttf) with score of 0.000000
findfont: Matching :family=STIXSize2:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXSize2 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXSiz2Sym.ttf) with score of 0.000000
findfont: Matching :family=STIXGeneral:style=italic:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXGeneral (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXGeneralItalic.ttf) with score of 0.000000
findfont: Matching :family=STIXNonUnicode:style=italic:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXNonUnicode (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXNonUniIta.ttf) with score of 0.000000
findfont: Matching :family=STIXNonUnicode:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXNonUnicode (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXNonUni.ttf) with score of 0.000000
findfont: Matching :family=cmb10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmb10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmb10.ttf) with score of 0.000000
findfont: Matching :family=cmtt10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmtt10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmtt10.ttf) with score of 0.000000
findfont: Matching :family=cmmi10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmmi10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmmi10.ttf) with score of 0.000000
findfont: Matching :family=cmex10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmex10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmex10.ttf) with score of 0.000000
findfont: Matching :family=cmsy10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmsy10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmsy10.ttf) with score of 0.000000
findfont: Matching :family=cmr10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmr10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmr10.ttf) with score of 0.000000
findfont: Matching :family=cmss10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmss10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmss10.ttf) with score of 0.000000
with the same line but this time setting the font to ‘Helvetica’, I get:
matplotlib version 0.98.5.2
Using fontManager instance from /Users/perf/.matplotlib/fontList.cache
backend pdf version unknown
findfont: Could not match :family=sans-serif:style=normal:variant=normal:weight=normal:stretch=normal:size=medium. Returning /Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/Vera.ttf
findfont: Matching :family=STIXGeneral:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXGeneral (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXGeneral.ttf) with score of 0.000000
findfont: Matching :family=STIXNonUnicode:style=normal:variant=normal:weight=bold:stretch=normal:size=12.0 to STIXNonUnicode (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXNonUniBol.ttf) with score of 0.000000
findfont: Matching :family=STIXGeneral:style=normal:variant=normal:weight=bold:stretch=normal:size=12.0 to STIXGeneral (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXGeneralBol.ttf) with score of 0.000000
findfont: Matching :family=STIXSize3:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXSize3 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXSiz3Sym.ttf) with score of 0.000000
findfont: Matching :family=STIXSize4:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXSize4 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXSiz4Sym.ttf) with score of 0.000000
findfont: Matching :family=STIXSize5:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXSize5 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXSiz5Sym.ttf) with score of 0.000000
findfont: Matching :family=STIXSize1:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXSize1 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXSiz1Sym.ttf) with score of 0.000000
findfont: Matching :family=STIXSize2:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXSize2 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXSiz2Sym.ttf) with score of 0.000000
findfont: Matching :family=STIXGeneral:style=italic:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXGeneral (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXGeneralItalic.ttf) with score of 0.000000
findfont: Matching :family=STIXNonUnicode:style=italic:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXNonUnicode (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXNonUniIta.ttf) with score of 0.000000
findfont: Matching :family=STIXNonUnicode:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to STIXNonUnicode (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/STIXNonUni.ttf) with score of 0.000000
findfont: Matching :family=cmb10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmb10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmb10.ttf) with score of 0.000000
findfont: Matching :family=cmtt10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmtt10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmtt10.ttf) with score of 0.000000
findfont: Matching :family=cmmi10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmmi10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmmi10.ttf) with score of 0.000000
findfont: Matching :family=cmex10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmex10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmex10.ttf) with score of 0.000000
findfont: Matching :family=cmsy10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmsy10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmsy10.ttf) with score of 0.000000
findfont: Matching :family=cmr10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmr10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmr10.ttf) with score of 0.000000
findfont: Matching :family=cmss10:style=normal:variant=normal:weight=normal:stretch=normal:size=12.0 to cmss10 (/Library/Python/2.5/site-packages/matplotlib/mpl-data/fonts/ttf/cmss10.ttf) with score of 0.000000
any idea what might be wrong here?