问题描述
我有这个 python 片段:
from pyx import *
from pyx import text
text.set(mode="latex")
text.preamble(r"\usepackage{amssymb}")
text.preamble(r"\usepackage{amsmath}")
c.text(-0.5,0.1,r"\huge{$\frac{8}{3}$}",[text.halign.Boxcenter])
由于错误而失败:
The expression passed to TeX was:
\ProcesspyXBox{\gdef\PyXBoxHAlign{0.50000}\huge{$\frac{8}{3}$}%
}{1}%
\PyXInput{5}%
After parsing the return message from TeX,the following was left:
*
*! Undefined control sequence.
<recently read> \frac
<argument> ...PyXBoxHAlign {0.50000}\huge {$\frac
(cut after 5 lines; use errordetail.full for all output)
这只发生在 \frac
中,如果我打印的是一个符号而不是分数,比如 5,它就可以正常工作。
解决方法
解决方案是您应该在创建画布之前调用所有文本操作:
text.set(text.LatexEngine,texenc='utf-8')
text.preamble(r'\usepackage[utf8]{inputenc}')
text.preamble(r"\usepackage{amssymb}")
text.preamble(r"\usepackage{amsmath}")
text.preamble(r"\usepackage{amsfonts}")
c = canvas.canvas().layer("aa")