任意两点间斜剖面做法总结【利用GRADS自带函数】

Jennifer

我现在就是要画这个图，但是有三个格点中心，举一反三试试看行不行。

海蓝蓝

maskout

maskout(expr,mask)

Wherever the mask values are less than zero, the values in expr are set to the missing data value.

Works with gridded or station data. Where mask values are positive, the expr values are not modified. Thus the result of maskout is data with a possibly increased number of missing data values. The maskout function, in spite of its apparant simplicity, is extremely useful.

Usage Notes

Examples

See the Examples for the const function for a description of using maskout to calculate the percentage of the globe covered by precipitation.
The maskout function can be used to cause part of the data to be ignored while doing another calculation. For example, if we have a land-sea mask, where sea values are negative, and we want to take some areal average of a quantity only over land:
d aave(maskout(p,mask.2),lon=0,lon=360,lat=0,lat=90)
People frequently have trouble using a mask grid, because it is often put into a seperate file, and given some arbitrary date/time and level. Thus, it is often necessary to locally override the dimension environment while using the mask grid:
d aave(maskout(p,mask.2(t=1)),lon=0,lon=360,lat=0,lat=90)
would probably be how Example 2 would have to be expressed in order to work, with the local override of t=1 specified on the mask data. See the documentation on how GrADS evaluates expressions within the dimension environment for more information.

river

海蓝蓝 发表于 2014-12-12 13:27
maskout

maskout(expr,mask)

是不是回复错了？

pangpang1128

感谢分享，学习中

寻路人

-omega.1*100,请恕我愚笨，.1是什么意思？

zhukefu

坐标不好整

river

寻路人 发表于 2014-12-16 20:58
-omega.1*100,请恕我愚笨，.1是什么意思？

那不是你笨，这个.1是文件号啊，意思是打开的第一文件里的变量。还有可能有.2  .3  .4 之类的，为了区分不同文件里的变量用的

lnsqxt

真的不错！会成为经典的！

taylor926

不錯,厉害~~~

lnsqxt

学习啦，谢谢楼主分享~~