If statement - matlab programming, MATLAB in Statistics

Assignment Help:

The IF Statement:

The if statement selects whether or not the other statement, or group of statements, is executed. The common form of the if statement is as shown below:

if condition

   action

end

The condition is a relational expression which is theoretically, or logically, either true or false. Action is a statement, or a group of statements, which will be executed when the condition is true. Whenever the if statement is executed, the condition is initially computed. If the value of the condition is theoretically true, the action will be executed, and if not, then the action will not be executed. The action can be several number of statements awaiting the reserved word end; the action is obviously bracketed by the reserved words if and end. (Note: This is dissimilar from the end which is used as an index into the vector or matrix.)

For illustration, the if statement below confirms to see whether the value of a variable is negative. When it is, the value changed to a positive number by using the absolute value function; or else nothing is changed.

if num < 0

num = abs(num)

end

When statements can be entered in the Command Window, though they usually make more sense in the scripts or functions. In the Command Window, if the line would be entered, then press the Enter key, then action, then Enter key, and finally end and Enter; the outcome will instantly follow. For illustration, the earlier if statement is shown twice here. Note that the output from the assignment is not suppressed; therefore the result of the action will be shown if the action is executed. At first time the value of the variable is negative therefore the action is executed and the variable is modified, but in the second situation the variable is positive therefore the action is skipped.

>> num = -4;

>> if num < 0

num = abs(num)

end

num =

4

>> num = 5;

>> if num < 0

num = abs(num)

end

>> 

This might be used, for illustration, to make sure that the square root function is not used on a negative number. The script below prompts the user for a number, and prints the square root. When the user enters a negative number, then the if statement changes it to positive before taking the square root.

1428_if statement.png


Related Discussions:- If statement - matlab programming

Data structure layers, Data structure layers: There are many layers in...

Data structure layers: There are many layers in this variable. For illustration,  cyls is the whole data structure, that is a vector of structs  cyls(1) is a separate

Functions which return values versus printing, Functions which return Value...

Functions which return Values versus printing: Also, the function which computes and returns values (throughout the output arguments) does not generally print them; that is le

Core objects, Core Objects: The Core Objects in MATLAB are the very fu...

Core Objects: The Core Objects in MATLAB are the very fundamental graphics primitives. The description can be found under the MATLAB Help: Under the Contents tab, click the Ha

Illustration of indexing, Illustration of Indexing: Though, rather tha...

Illustration of Indexing: Though, rather than of creating the index vector manually as shown here, the process to initialize the index vector is use to a sort function. The al

Illustration of tracing a error, Illustration of tracing a error: The ...

Illustration of tracing a error: The one way of following the flow of function, or tracing it, is to use the echo function. The echo function, that is a toggle, will show each

Fopen function - file function, fopen function - file function: The fo...

fopen function - file function: The fopen opens the file for reading. The fscanf then reads each line one double and one character, and put each pair in individual columns in

Vectorizing, Vectorizing: In most of the cases in MATLAB, loops are no...

Vectorizing: In most of the cases in MATLAB, loops are not essential. As MATLAB is written specifically to work with the vectors and matrices, most operations can be completed

Function polyval - interpolation, Function polyval - interpolation: Th...

Function polyval - interpolation: The function polyval can then be used to compute the polynomial at particular values. For illustration, we could compute at every value in th

Steps for input output functions - lower level file, Steps for input output...

Steps for input output functions - Lower level file: The steps involved are as shown below:  Open the file.  Read the file, write to the file, or append to the file.

Advanced file input and output, Advanced File Input and Output: In tha...

Advanced File Input and Output: In that section, we saw how to read the values entered by user using the input as well as the output functions disp and fprintf, that shows inf

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd