free grads

open

open filename

Opens filename, which should be the name of a grads data descriptor file, also called a control file. 

Usage Notes

1. The standard file extension for grads data descriptor files is .ctl. Provided you adhere to this standard, there is no need to type the extension .ctl when issuing the open command.

   
   

2. You will need to open at least one data-descriptor file before you can enter other grads commands.

   
   

3. You can open more than one data-descriptor file. Each file is numbered according to the order in which it was opened.

Examples

Both of these commands will have the same effect -- opening the grads data descriptor file "jandata.1966.ctl".