When I use matplotlib's internal tex (rcParams['text.useTex']=False), the postscript files generated cause errors that look like this when you try to ps2pdf them: ps2pdf h2co_pilot.psError: /rangecheck in --get--Operand stack: --dict:20/25(ro)(L)-- --nostringval-- 71Execution stack: %interp_exit .runexec2 --nostringval-- --nostringval-- --nostringval-- 2 %stopped_push --nostringval-- --nostringval-- --nostringval-- false 1 %stopped_push 1862 1 3 %oparray_pop 1861 1 3 %oparray_pop 1845 1 3 %oparray_pop 1739 1 3 %oparray_pop --nostringval-- %errorexec_pop .runexec2 --nostringval-- --nostringval-- --nostringval-- 2 %stopped_push --nostringval-- %finish_show --nostringval-- --nostringval-- 9 6 0 --nostringval-- (pdf_text_enum_t) %op_show_continue --nostringval--Dictionary stack: --dict:1147/1684(ro)(G)-- --dict:0/20(G)-- --dict:70/200(L)-- --dict:116/300(L)-- --dict:44/200(L)-- --dict:25/42(L)--Current allocation mode is localLast OS error: 2Current file position is 791626GPL Ghostscript 8.64: Unrecoverable error, exit code 1make: *** [h2co_pilot.pdf] Error 1 They will not open in MacOS's Preview.app either. Solution: Make figures with rcParams['text.useTex'] = True