求助！用grads将流线和阴影画在一起时遇到了问题！

木木央

'reinit'
'sdfopen e:\uwind\uwnd.2015.nc'
'sdfopen e:\vwind\vwnd.2015.nc'
'sdfopen e:\air\air.2015.nc'
'sdfopen e:\hgt\hgt.2015.nc'
'sdfopen e:\rhum\rhum.2015.nc'
由于计算的是平均场，因此先求好平均值
'set lev 850'
'set lon 60 160'
'set lat 0 70'
'set grads off'
'set grid off'
'set mpdset cnriver'
'define u=ave(uwnd,t=693,t=788,1)'
'define v=ave(vwnd.2,t=693,t=788,1)'
'define a=ave(air.3-273.5,t=693,t=788,1)'
'define h=ave(hgt.4,t=693,t=788,1)'
'define r=ave(rhum.5,t=693,t=788,1)'
以下是计算水汽通量散度场，也就是阴影场（为了去掉空白边，计算时先取了较大范围，绘制时取了较小范围，所以d了两次）
'set lev 850'
'set lon 60 160'
'set lat 0 70'
'set grads off'
'set grid off'
'set mpdset cnriver'
'set gxout shaded'
'define p=lev'
'define e=(6.112*exp((17.67*(a-273.16))/(a-29.65)))'
'define qs=(0.622*e/(p-0.378*e))'
'define q=qs*r/100'
'define qdiv=hdivg(q*u/9.8,q*v/9.8)'
'd qdiv*10000000'
'c'
'set lev 850'
'set lon 70 150'
'set lat 10 60'
'set grads off'
'set grid off'
'set mpdset cnriver'
'set gxout shaded'
'd qdiv*10000000'
以下是绘制风场流线图和温度场流线图

'set lev 850'
'set lon 70 150'
'set lat 10 60'
'set grads off'
'set grid off'
'set mpdset cnriver'
'set gxout stream'
'd u;v'
'set lev 850'
'set lon 70 150'
'set lat 10 60'
'set grads off'
'set grid off'
'set mpdset cnriver'
'set gxout stream'
'set ccolor 2'
'set cthick 5'
'd a'
'draw title 850hPa 0623-0716 average'
'printim e:\sy1\850.png white'
;

木木央

如果将画流场的部分程序删除，就会变成下图这样