Illustration of reading from files, MATLAB in Statistics

Illustration of reading from files:

For illustration, suppose that there is a data file 'subjexp.dat' that has on each line a number followed by thecharacter code. The type function can be used to show the contents of this file (as the file does not have the default extension .m, the extension on the filename should be involved).

>> type subjexp.dat

5.3 a

2.2 b

3.3 a

4.4 a

1.1 b

 

The load function would not be capable to read this into the matrix as it holds both numbers and text. Rather than, the fgetl function can be used to read each line as a string and then the string functions are used to break up the numbers and characters. For illustration, the below just reads each line and prints the number with 2 decimal positions and then the rest of the string:

1648_Illustration of reading from files.png

2340_Illustration of reading from files1.png

Here is an illustration of executing this script:

>> fileex

5.30 a

2.20 b

3.30 a

4.40 a

1.10 b

File close successful

In this illustration, in the loop each and every time the fgetl function reads one line into the string variable. The string function strtok is then used to store the number and character in individual variables, both of which are the string variables. The function str2num should then be used to convert the number stored in the string variable into a double variable so that computations could be performed on it.

Rather than of using the fgetl function to read one line, a file has been once opened the fscanf function could be used to read in from this file directly into a matrix.

Though, the matrix should be manipulated somewhat to get it back into the unique form from the file. The format of using the function is as shown below:

mat = fscanf(fid, 'format', [dimensions])

Posted Date: 10/20/2012 6:24:04 AM | Location : United States







Related Discussions:- Illustration of reading from files, Assignment Help, Ask Question on Illustration of reading from files, Get Answer, Expert's Help, Illustration of reading from files Discussions

Write discussion on Illustration of reading from files
Your posts are moderated
Related Questions
Functions which complete a task without returning Values: Most of the functions do not compute values, but instead of accomplish a task like printing formatted output. As thes

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

Run-time or execution-time error: The Run-time, or execution-time, errors are found whenever a script or function is executing. With most of the languages, an illustration of

Rectangle - graphics objects: The other core graphics object is the rectangle that can have curvature added to it (!!). Merely calling the function rectangle without any argum

Persistent Variables: Generally, whenever a function stops executing, then the local variables from that function are cleared. That means that each and every time a function i

WHILE Loops: The while statement is used as a conditional loop in MATLAB; it is used to repeat an action whenever ahead of the time it is not known how many times the action w

Vectors of nested structures: The Combining vectors and nested structures are possible to have a vector of structures in which several fields are structures themselves. Here i

Program of Persistent variables: The program below elaborates this. The script calls a function func1 that initializes a variable count to 0, then increment it, and print the

Indexing: The Indexing is an alternate to sort a vector. With indexing, the vector is left in its original order. An index vector is used to point values in the original vecto

Combining Nested FOR Loops and the IF Statements: The statements inside a nested loop can be any of the valid statement, involving any selection statement. For e.g., there can