1.4.2 - Command Input
Enroll to start learning
You’ve not yet enrolled in this course. Please enroll for free to listen to audio lessons, classroom podcasts and take practice test.
Interactive Audio Lesson
Listen to a student-teacher conversation explaining the topic in a relatable way.
Introduction to SCILAB
🔒 Unlock Audio Lesson
Sign up and enroll to listen to this audio lesson
Today, we're going to learn about SCILAB, a powerful software similar to MATLAB. Can anyone tell me what SCILAB is used for?
It's used for numerical calculations, right?
Exactly! It's great for tasks like solving equations and generating graphics. Now, has anyone attempted to install SCILAB?
I tried, but I wasn't sure where to start.
Let’s walk through that. To install SCILAB, you need to visit the official SCILAB website and download the installation file. Can you remember the steps we’ll take to download it?
Do we need to make sure we have enough space on our hard drive?
Yes! SCILAB approximately requires 50 MB. So now, let’s summarize: first, we download the installer, then we run it and follow the prompts. Great job today!
Basic Commands and Operations
🔒 Unlock Audio Lesson
Sign up and enroll to listen to this audio lesson
Let’s dive into SCILAB’s functionalities! Can someone give an example of a simple arithmetic operation we can perform?
How about adding two numbers?
Exactly! In SCILAB, we can assign a value like `a = 5`. After that, if we want to find `a + 3`, what command do we use?
We just type `a + 3`.
Great! And how about using special constants like π and e? Can anyone recall what they represent?
π is the ratio of the circumference to the diameter, and e is the base of the natural logarithms!
Correct! Remember to use `%pi` for π and `%e` for the natural base. This is how we extend our calculations with SCILAB.
Working with Vectors and Matrices
🔒 Unlock Audio Lesson
Sign up and enroll to listen to this audio lesson
Now, let’s move on to vectors. How do we create a vector in SCILAB?
We can use square brackets and separate values with commas!
Correct! For example, we can define `v = [1, 2, 3]`. What operation can we perform with vectors?
We can add them together!
Yes, if we have two vectors `u` and `v`, we can type `u + v`. Can someone tell me how to do matrix multiplication in SCILAB?
We use the `*` operator to multiply two matrices together!
Exactly! Matrix operations are crucial for scientific computations. Keep practicing, and you'll be amazed by what SCILAB can do!
Introduction & Overview
Read summaries of the section's main ideas at different levels of detail.
Quick Overview
Standard
The section provides an overview of SCILAB, detailing how to download, install, and begin using the software for numerical calculations and programming tasks, along with examples of basic commands for arithmetic operations and matrix manipulations.
Detailed
Detailed Summary
This section provides a comprehensive introduction to SCILAB, a free numerical, programming, and graphics environment similar to MATLAB. It begins with straightforward instructions on how to download and install SCILAB, specifically for Windows but notes that installation on other operating systems is similarly accessible via the SCILAB website. The section describes SCILAB's features, highlighting its capacity for basic arithmetic, algebraic operations, graphics generation, programming functions, and solving linear algebra problems.
SCILAB is characterized as a self-contained package that occupies roughly 50 MB on your hard disk. The documentation retrieval process is explained, directing users to resources available via the SCILAB main webpage, including various tutorials and guides.
The section emphasizes the foundational command input used in SCILAB, illustrated through various arithmetic exercises involving scalar operations, special constants, and matrix manipulations. It encourages hands-on exploration of commands as users interactively engage with the software. Furthermore, the utility of the help feature within SCILAB is discussed, along with an overview of the interface's structure, including file management, command history, and execution of scripts. Examples are provided for both simple arithmetic and more complex operations, ensuring users grasp SCILAB’s capabilities immediately.
Youtube Videos
Audio Book
Dive deep into the subject with an immersive audiobook experience.
Reading Commands from a Script File
Chapter 1 of 3
🔒 Unlock Audio Chapter
Sign up and enroll to access the full audio experience
Chapter Content
You can read SCILAB commands from a script file, which is basically a text file listing all the commands you want to use. For example, create the following text file in the bin subdirectory of the SCILAB directory using NOTEPAD, and call it session2.txt:
//--------------------------------------------------------------------------
clear
A = [1. 2. -3. // entering
3. 4. 5. // elements of
7. 8. 9.] // matrix A
b = [1.; 2.; 3.] // enter vector b
xa = inv(A)*b // calculate x using matrix inverse
xb = linsolve(A,b) // calculate x using SCILAB's own linsolve function
//--------------------------------------------------------------------------
Then, press Restart in SCILAB, and type: exec('session2.txt')
You will see SCILAB execute all the commands in your file, stopping at the end of the file.
Detailed Explanation
This chunk talks about how SCILAB allows you to automate commands by placing them into a text file called a script. By creating a text file with SCILAB commands, you can easily execute a series of operations without typing each command manually. The text file should be saved in a specific location called the bin subdirectory within the SCILAB directory. When you execute the command 'exec('session2.txt')', SCILAB reads and runs all the commands in that file sequentially, just as if you had typed them in one by one.
Examples & Analogies
Imagine you're a chef following a recipe from a cookbook. Instead of remembering and writing down each step for cooking a dish every time you want to make it, you write down the entire recipe in your personal recipe book. Then, each time you want to cook that dish, you just follow the step-by-step guidelines. Similarly, using a script file in SCILAB allows you to save your commands and run them easily, just like following a recipe.
SCILAB Command History
Chapter 2 of 3
🔒 Unlock Audio Chapter
Sign up and enroll to access the full audio experience
Chapter Content
All commands entered in a given SCILAB session get stored into a SCILAB command history buffer. The commands are thus accessible for re-use or edition. All the command history functions are available through the option History under the File menu in the SCILAB worksheet. The most useful commands are cntl-P and cntl-N, which lets you access the previous command or the next command, respectively, in the command history buffer.
Detailed Explanation
SCILAB keeps track of every command you enter during a session in a command history buffer. This means you do not have to re-type commands that you have previously used; instead, you can simply use keyboard shortcuts like ctrl-P (to go back to the previous command) and ctrl-N (to go forward to the next command) to navigate through your command history. This is particularly useful for correcting mistakes or executing commands that you want to run multiple times.
Examples & Analogies
Think of the command history as a chalkboard where you write down all your calculations in a classroom. If you want to repeat a certain calculation or check what you did earlier, you can easily look back at the chalkboard instead of starting from scratch. The command history allows you to quickly revisit your previous commands, similar to glancing at your notes to recall the steps you took in a math problem.
Selective Worksheet Output
Chapter 3 of 3
🔒 Unlock Audio Chapter
Sign up and enroll to access the full audio experience
Chapter Content
Suppose you have been working on a lengthy SCILAB session whose command history buffer contains some results that produced errors as well as some intermediary results that are not of interest to you for output. For your output, you can select only those commands relevant to your final results by using Cntl-P and Cntl-N.
Detailed Explanation
When working in SCILAB, after running many commands, you might find that not all results are useful or relevant for your final output. By using the command history navigation (with ctrl-P and ctrl-N), you can filter and select only the commands that produce meaningful results. This is beneficial when you want to create a clean report or save only important computations instead of cluttering with commands that led to errors or were only intermediate steps.
Examples & Analogies
It's akin to editing a long written essay. After writing, you review it to cut out unnecessary sentences or spelling mistakes, keeping only what is essential for the final version. The same applies to SCILAB; you can sift through the commands executed and ensure only the useful parts are captured in your report or documentation.
Key Concepts
-
Numerical Environment: SCILAB is a programming environment that supports numerical operations.
-
Download and Install: Instructions for obtaining SCILAB from its official website.
-
Command Syntax: Understanding the basic syntax for entering commands in SCILAB.
Examples & Applications
Example of assigning a value: a = 5 and performing operations such as a + 3.
Creating a vector: v = [1, 2, 3] and adding two vectors u + v.
Memory Aids
Interactive tools to help you remember key concepts
Rhymes
SCILAB's the tool that's quite capable, for math and more, it’s simply irreplaceable.
Stories
Imagine using SCILAB as a magician would use spells to conjure numbers from thin air, mastering each command like a potion for perfect calculations.
Memory Tools
To remember command usage: Assignments Are Kind to Everyone (A = variable; A = value).
Acronyms
To recall SCILAB functionalities, think of ‘SIMPLES’ - Solve, Input, Matrix, Plot, Evaluate, Learn, Script.
Flash Cards
Glossary
- SCILAB
A free numerical, programming and graphics environment similar to MATLAB.
- Matrix
A rectangular array of numbers arranged in rows and columns.
- Vector
A one-dimensional array that can hold multiple values.
- Constant
A fixed value that does not change during a program execution.
- Command
An instruction given to SCILAB to perform a certain action.
Reference links
Supplementary resources to enhance your learning experience.