Difference between revisions of "Scilab/C4/User-Defined-Input-and-Output/English"

• Input Function
• Formatting the Output
• save function
• load function

You should have

1. Basic knowledge of Scilab.
2. If not, for relevant tutorials please visit spoken hyphen tutorial dot org

For Demonstration: Ubuntu Linux12.04 operating system is used with Scilab version 5.3.3 installed

The input() function

• is used to take the input from the user.
• provides a prompt in the text string for user input.
• waits for input from the keyboard.

If nothing but a carriage return is entered at the prompt, input() function returns an empty matrix.

In the second example, the second argument is “string”.

So the output is a character string, which is the expression entered using the keyboard.

--> x = input (“ Enter your age”)

--> y = input (“ Enter your age”, “string”)

-->x is equal to input open bracket inside double quotes Enter your age colon close the bracket

I will enter a number say 25 here.

Its shows the output as

x =

25.

Now type

-->y is equal to input open bracket inside double quotes Enter your age comma inside double quotes string close the bracket.

I will enter a number say 25 here.

Its shows the output

y =

25

We are doing this to validate the use and importance of the argument “string”, given in the second example.

-->typeof(y)

-->typeof(x)

ans is equal to

constant

-->typeof(y)

ans =

string

• the first answer stored in x is of type constant and
• second answer stored in y, with the argument “string” included in the command, is of type string.

This can be done using the mprintf() function.

mprintf() function converts, formats and writes data on to the Scilab console.

It is an interface for C-coded version of printf function.

Type the following on the Scilab Console

-->mprintf("Value of x=%d is taken as a CONSTANT, while value of y=%s is taken as a STRING", x , y)

Value of x=25 is taken as a CONSTANT,while value of y=25

is taken as a STRING

In the above example

• percentage d is used to insert an constant data stored in variable x and
• percentage s is used to insert a string data stored in variable y.

To quit Scilab midway through a calcula-

tion and

continue at a later stage type

--> save thissession

This will save the current values of all variables to a file

called thissession.

This file cannot be edited.

It is in binary format.

When you next start Scilab, type

--> load thissession

and the computation can be resumed where you left off.

The purpose of save and load function are

• The save() command saves the scilab current variables in a binary file.
• If the variable is a graphic handle, the save function saves all the corresponding graphics_entities definition.
• The file can be given either by its paths or by its descriptor previously given.

• save(fd) saves all current variables in the file defined by the descriptor fd.
• save(filename,x,y) or save(fd,x,y) saves only named variables x and y.

--> a = eye(2,2)

a =

1. 0.

0. 1.

--> b = ones (a)

b =

1. 1.

1. 1.

--> save('matrix-a-b.dat', a, b)

Let us define two matrices say a and b

-->a = eye(2,2)

-->b=ones(a)

--> save matrix-a-b

or it can also be written as

-->save('matrix-a-b.dat',a,b)

This saves the values of variables in a binary file matrix-a-b.dat in the present working directory.

You can browse the present working directory to check the existence of this binary file.

-->clear a b

Before this, let us clear the variables a and b

-->clear a space b

Let us cross check if these variables are really cleared.

-->a

!--error 4

Undefined variable: a

-->b

!--error 4

Undefined variable: b

--> load('matrix-a-b.dat', 'a', 'b')

Load open bracket open single quote matrix dash a dash b dot dat close quotes comma inside quotes a comma inside quotes b close the bracket

a =

1. 0.

0. 1.

--> b

b =

1. 1.

1. 1.

-->a

-->b

You can see the values are loaded back in the variables.

• Input Function using input command

• Formatting the Output using mprintf command
• Save Function
• Load Function

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