grads绘图直接绘制假相当位温和逐层提取后在绘制图不一样，麻烦帮找下原因

243196931@qq.co

*画相当位温相关图
'reinit'
********************************************* data ***
'open E:\taifeng\ctl\fnl_20200903_06_00.ctl'
'set grads off'
'set grid off'
'set timelab off'
'set lat 10 70'
'set lon 50 160'
'set lev 1000'
'define prs=lev'
'define e1=17.67*(TMPprs-273.15)/(TMPprs-29.65)'
'define es=6.112*exp(e1)'
'define qs=(0.62197*es/(prs-0.378*es))/100'
'define shum=rhprs*qs'
'define e=prs*shum/(0.62197+shum)'
'define tk=55.0+2840.0/(3.5*log(TMPprs)-log(e)-4.805)'
'define th=TMPprs*pow((1000./prs),(0.2854*(1.0-0.28*shum)))'
'define the=th*exp(((3376/tk)-2.54)*shum*((1.0+0.81*shum)))'
'set grads off'
'set grid off'
'set gxout contour'
'set ccolor 1'
'set csmooth on'
'set cthick 7'
'd the'
'printim E:\taifeng\pic\thse1000.png white'
;
下面这个是论坛绘制湿位涡的一部分
'reinit'
'set gxout fwrite'
********************************************* data ***
'open E:\taifeng\ctl\fnl_20200903_06_00.ctl'
'set fwrite E:\taifeng\thse.dat'
*i=925
*while(i<=977)
'set lon 50 160'
'set lat 10 70'
*'set t 'i''
'set lev 1000'
'define prs=lev'
'define e1=17.67*(TMPprs-273.15)/(TMPprs-29.65)'
'define es=6.112*exp(e1)'
'define qs=(0.62197*es/(prs-0.378*es))/100'
'define shum=rhprs*qs'
'define e=prs*shum/(0.62197+shum)'
'define tk=55.0+2840.0/(3.5*log(TMPprs)-log(e)-4.805)'
'undefine e'
'define theta=TMPprs*pow((1000./prs),(0.2854*(1.0-0.28*shum)))'
'define thse=theta*exp(((3376/tk)-2.54)*shum*((1.0+0.81*shum)))'
'd thse'
'set lev 925'
'define prs=lev'
'define e1=17.67*(TMPprs-273.15)/(TMPprs-29.65)'
'define es=6.112*exp(e1)'
'define qs=(0.62197*es/(prs-0.378*es))/100'
'define shum=rhprs*qs'
'define e=prs*shum/(0.62197+shum)'
'define tk=55.0+2840.0/(3.5*log(TMPprs)-log(e)-4.805)'
'undefine e'
'define theta=TMPprs*pow((1000./prs),(0.2854*(1.0-0.28*shum)))'
'define thse=theta*exp(((3376/tk)-2.54)*shum*((1.0+0.81*shum)))'
'd thse'
'set lev 850'
'define prs=lev'
'define e1=17.67*(TMPprs-273.15)/(TMPprs-29.65)'
'define es=6.112*exp(e1)'
'define qs=(0.62197*es/(prs-0.378*es))/100'
'define shum=rhprs*qs'
'define e=prs*shum/(0.62197+shum)'
'define tk=55.0+2840.0/(3.5*log(TMPprs)-log(e)-4.805)'
'undefine e'
'define theta=TMPprs*pow((1000./prs),(0.2854*(1.0-0.28*shum)))'
'define thse=theta*exp(((3376/tk)-2.54)*shum*((1.0+0.81*shum)))'
'd thse'
'set lev 700'
'define prs=lev'
'define e1=17.67*(TMPprs-273.15)/(TMPprs-29.65)'
'define es=6.112*exp(e1)'
'define qs=(0.62197*es/(prs-0.378*es))/100'
'define shum=rhprs*qs'
'define e=prs*shum/(0.62197+shum)'
'define tk=55.0+2840.0/(3.5*log(TMPprs)-log(e)-4.805)'
'undefine e'
'define theta=TMPprs*pow((1000./prs),(0.2854*(1.0-0.28*shum)))'
'define thse=theta*exp(((3376/tk)-2.54)*shum*((1.0+0.81*shum)))'
'd thse'
'set lev 600'
'define prs=lev'
'define e1=17.67*(TMPprs-273.15)/(TMPprs-29.65)'
'define es=6.112*exp(e1)'
'define qs=(0.62197*es/(prs-0.378*es))/100'
'define shum=rhprs*qs'
'define e=prs*shum/(0.62197+shum)'
'define tk=55.0+2840.0/(3.5*log(TMPprs)-log(e)-4.805)'
'undefine e'
'define theta=TMPprs*pow((1000./prs),(0.2854*(1.0-0.28*shum)))'
'define thse=theta*exp(((3376/tk)-2.54)*shum*((1.0+0.81*shum)))'
'd thse'
'set lev 500'
'define prs=lev'
'define e1=17.67*(TMPprs-273.15)/(TMPprs-29.65)'
'define es=6.112*exp(e1)'
'define qs=(0.62197*es/(prs-0.378*es))/100'
'define shum=rhprs*qs'
'define e=prs*shum/(0.62197+shum)'
'define tk=55.0+2840.0/(3.5*log(TMPprs)-log(e)-4.805)'
'undefine e'
'define theta=TMPprs*pow((1000./prs),(0.2854*(1.0-0.28*shum)))'
'define thse=theta*exp(((3376/tk)-2.54)*shum*((1.0+0.81*shum)))'
'd thse'
'set lev 400'
'define prs=lev'
'define e1=17.67*(TMPprs-273.15)/(TMPprs-29.65)'
'define es=6.112*exp(e1)'
'define qs=(0.62197*es/(prs-0.378*es))/100'
'define shum=rhprs*qs'
'define e=prs*shum/(0.62197+shum)'
'define tk=55.0+2840.0/(3.5*log(TMPprs)-log(e)-4.805)'
'undefine e'
'define theta=TMPprs*pow((1000./prs),(0.2854*(1.0-0.28*shum)))'
'define thse=theta*exp(((3376/tk)-2.54)*shum*((1.0+0.81*shum)))'
'd thse'
'set lev 300'
'define prs=lev'
'define e1=17.67*(TMPprs-273.15)/(TMPprs-29.65)'
'define es=6.112*exp(e1)'
'define qs=(0.62197*es/(prs-0.378*es))/100'
'define shum=rhprs*qs'
'define e=prs*shum/(0.62197+shum)'
'define tk=55.0+2840.0/(3.5*log(TMPprs)-log(e)-4.805)'
'undefine e'
'define theta=TMPprs*pow((1000./prs),(0.2854*(1.0-0.28*shum)))'
'define thse=theta*exp(((3376/tk)-2.54)*shum*((1.0+0.81*shum)))'
'd thse'
   j=1
   while(j<=8)
   'set lon 50 160'
   'set lat 10 70'
* 'set t 'i''
   'set z 'j''
   'd ugrdprs'
    j=j+1
    endwhile
    j=1
   while(j<=8)
   'set lon 50 160'
   'set lat 10 70'
*   'set t 'i''
   'set z 'j''
   'd vgrdprs'
    j=j+1
    endwhile
*i=i+1
*endwhile
'disable fwrite'
'reinit'

之后写的ctl绘制
DSET E:\taifeng\thse.dat
TITLE Upper Data
undef -9.99E33
xdef 45 linear 50 2.5
ydef 25 linear 10 2.5
zdef 8 levels 1000 925 850 700 600 500 400 300
tdef 1 linear 0z20Aug2020 6hr
vars 3
thse 8 99 temps
ugrdprs 8 99 u-wind
vgrdprs 8 99 v-wind
Endvars
绘制图

'reinit'

'open E:\taifeng\gs\tfgs\shiweiwo\thse.ctl'
'set lat 10 70'
'set lon 50 160'
'set lev 1000'
'set gxout contour'
'set csmooth on'
'set cthick 7'
'd thse'


'printim E:\taifeng\pic\thse100.png white'

243196931@qq.co

一起研究下啊{:5_235:}{:5_235:}{:5_235:}

lqouc

fnl是2.5的分辨率吗？

伽蓝鸟

太长就不检查每行代码了，话说算假相当位温用ept这个内置函数就好了啊

小浪

e1=17.67*(TMPprs-273.15)/(TMPprs-29.65)'

puck66

伽蓝鸟 发表于 2021-1-28 22:04
太长就不检查每行代码了，话说算假相当位温用ept这个内置函数就好了啊

哪有eqt ？

伽蓝鸟

puck66 发表于 2021-11-27 21:11
哪有eqt ？

首先，是ept不是eqt。其次，这是个内置函数，算相当位温的。相当位温跟假相当位温非常接近，几乎可以视为等同的。
ept(T,RH,P)
This function computes the equivalent potential temperature in Kelvin given the Temperature T in Kelvin, the relative humidity RH in percent, and the pressure P in hPa.
直接调用就行了，不用整那么多行代码

puck66

伽蓝鸟 发表于 2021-11-28 11:21
首先，是ept不是eqt。其次，这是个内置函数，算相当位温的。相当位温跟假相当位温非常接近，几乎可以视为 ...

哦哦，，好哒~ 我去看看，3Q

puck66

伽蓝鸟 发表于 2021-11-28 11:21
首先，是ept不是eqt。其次，这是个内置函数，算相当位温的。相当位温跟假相当位温非常接近，几乎可以视为 ...

内置函数我run了一下，跟计算出来的确实相差不大~ 请问大佬，grads有些什么内置函数去哪里可以看到？我在官网的index似乎没有找到ept

伽蓝鸟

puck66 发表于 2021-12-8 23:10
内置函数我run了一下，跟计算出来的确实相差不大~ 请问大佬，grads有些什么内置函数去哪里可以看到？我在 ...

看你GrADS安装在了哪里，\opengrads2.1\Contents\Resources\Documentation\opengrads\doc\udxt