Frequently done errors ... (PSTricks web site에서 발췌)
Missing number, treated as zero This is the default error message when you are using symbolic node names without enabled \SpecialCoor after loading the pst-node package!
You cannot run your files with pdftex/pdflatex/luatex/lualatex, use xetex/xelatex instead or the sequence latex->dvips->ps2pdf, or see topic pdfoutput
linestyle=dashed doesn't work after an update of pstricks.tex. You should update also pstricks.pro and pstricks.sty.