编译安装NCL之后，运行NCL后出现如下错误，因为一直都没有用，所以都没发现。

[root@px: /root]# ncl
 Copyright (C) 1995-2015 - All Rights Reserved
 University Corporation for Atmospheric Research
 NCAR Command Language Version 6.3.0
 The use of this software is governed by a License Agreement.
 See http://www.ncl.ucar.edu/ for more details.
warning:Unable to Get System Resource File Name?
warning:Unable to load System Resource File (null)
fatal:GetSysAppDir:Unable to get a default value for the system App Resource directory
warning:["Resources.c":734]:Unable to set appSysDir to default value - Using NULL
fatal:GetSysAppDir:Unable to get a default value for the system App Resource directory
warning:["Resources.c":734]:Unable to set appSysDir to default value - Using NULL
warning:Unable to Get System Resource File Name?
warning:WorkstationClassInitialize:Unable to access rgb color database - named colors unsupported:[errno=2]
NDV_COLORMAP_PATH environment variable not set:
    defaulting to .:$NCARG_ROOT/lib/ncarg/colormaps
warning:["Palette.c":1844]:NhlLoadColormapFiles: Invalid directory encountered in colormap path specification
段错误 (core dumped)

解决方法也很简单，加个环境变量就可以了。之前我是源码下下来之后configure和make的，所以也没仔细看官方文档，没想到还要这个环境变量才能用。

如果是像我这样默认安装的，一般安装路径是/usr/local，所以使用export NCARG_ROOT=/usr/local就可以了。如果是其他路径，相应修改一下就可以了。把这句话加到相应的bashrc里，例如：如果是单个用户需要，就加到用户home目录下的.bashrc文件里，如果是所有用户，就加在/etc/bashrc里，之后重开终端。