Terminal CLI

Terminal CLI#

Running an OpenSees at the command line allows you to test the program and make sure you have set up the right environment. This is ideal for:

  • Testing syntax or exploring commands in real time

  • Building a small model step-by-step

  • Debugging specific lines of code without running an entire script

The CLI (Command-Line Interface) is a text-based way to interact with a computer program or operating system by typing commands into a Terminal or Console window, instead of using graphical elements like buttons and menus.

A CLI/Terminal allows you to:

  • Type commands to run programs, manage files, or perform tasks

  • See text-based output in response to commands

  • Work more efficiently through automation, scripting, and precise control

Most advanced scientific tools, such as OpenSees or python, are designed to be run through a command-line interface (CLI). This means you launch the application by typing a command into a terminal, which tells the operating system to start the program and process your input script.

CLI in the Context of OpenSees#

Suppose you want to run an OpenSees model:

  • In a graphical interface, you’d click through menus to load and run the model

  • In a CLI, you’d type: OpenSees model.tcl

This command immediately runs the model file using OpenSees.

The CLI allows you to:

  • Enter OpenSees commands one-by-one and see immediate results

  • Debug models interactively by modifying and re-running commands

  • Run both Tcl and Python (OpenSeesPy) scripts directly from the terminal

Why Use a the Terminal?#

Advantage

Description

Speed

Tasks can be completed quickly using short commands

Automation

Enables scripting to automate repetitive processes

Control

Provides more detailed access to program features and settings

Remote Access

Allows access to remote servers via SSH or other terminals

Accessing the Terminal#

You can access the terminal through the Jupyter interface.

Becoming familiar with how to open and use a terminal is the first step to unlocking the full power of command-line tools like OpenSees on both local and remote systems.

Access the terminal through the Jupyter interface by clicking “New > Terminal” in the Jupyter file browser or clicking the Terminal icon in the Launcher.

Basic Linux Commands#

Here are the basic commands you may need when navigating the CLI in a linux environment.
mkdir dirname          : make a new directory
cd dirname             : change directory
pwd                    : returns current directory
ls                     : list files 
cp origFile newFile    : copy a file
mv origFile newFile    : move a file
rm filename            : remove a file
wc –l directoryname    : how many files in a directory 
wc –l filename         : how many lines in a file

Tip: In Jupyter Hub, you can do most file operations through the navigation pane, but knowing these commands is crucial for work on the HPC.

Summary#

The Command-Line Interface (CLI) at the Terminal is a fast, powerful, and flexible way to use OpenSees and other scientific tools. It’s especially helpful in high-performance computing (HPC) environments where speed, automation, and control are essential.

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