Print, fprint, fscanf, and disp functions of MATLAB

Print, fprint, fscanf, and disp functions of MATLAB

Print:

The print function can save the function image as an image:

 
Minbnd =-4 * PI; maxbnd = 4 * PI; t = minbnd: 0.1 * Pi: maxbnd; plot (T, sin (t), 'G', 'linewidth ', 2); line ([minbnd, maxbnd], [0, 0]); % draw the X axis ([-10, 10,-2, 2]) % defines the displayed coordinate range: X Between (-10, 10), y between (-2, 2) grid between '); % Save As PNG image, in the current working directory of MATLAB
 

As follows:

Open the work directory of Step 7 and you will be able to see the sin.png image.

Print ('-dpng', 'sin.png' must be saved as a PNG image, and the file name is sin.png. The first parameter can be:

-Dbmp: Save As BMP

-Djpeg: Save As JPEG

-Dpng: Save As PNG

-Dpcx: Save As PCX format

-Dpdf: Save as PDF

-Dtiff: Save As tiff

Fprintf:

The fprintf function can write data to a text file in the specified format:

 
Data = [5, 1, 2; 3, 7, 4]; [row, Col] = size (data); for I = 1: Row for j = 1: col fprintf ('data (% d, % d) = % d \ n', I, j, data (I, j); % output directly to the screen; similar to the C language output format endend
 

FID in fprintf (FID, format, data) indicates the file handle opened by the fopen function. If FID is omitted, it is directly output to the screen. format is the output format in string format, data is the data to be output. The format can be:

% C single character % d signed decimal number (% I can also) % u unsigned decimal number % F floating point number (% 8.4f indicates taking the 8-Bit Width of the floating point number, at the same time, 4 decimal places) % O unsigned octal digits % s string % x lowercase a-f hexadecimal digits % x size a-f hexadecimal digits
 

Output to file:

 
Data = [5, 1, 2; 3, 7, 4]; [row, Col] = size (data ); % calculate the number of rows and columns of matrix data % add t to output line breaks in Windows format, that is, 0xod 0x0a, without Tsung output line breaks in linuxformat, I .e. 0x0afid1_fopen('test.txt ', 'wt'); % open the file for I = 1: row for j = 1: Col fprintf (FID, '% d', data (I, j); % similar to the output format of end fprintf (FID, '\ n'); endfprintf (FID, 'This is a string \ n'); fprintf (FID,' % x', hex2dec ('abcd ')); fclose (FID); % do not forget to close the file!
 

The test.txt file will be generated in the work directory of the previous project named "Matlab ".

Read from file:

We can use the fscanf function.

Fscanf:

 
% The reason for adding T is the same as above: FID = fopen ('d: \ test.txt ', 'rt'); % read data to data. Where data is a matrix of 2*3 data = fscanf (FID, '% d', [2, 3]); s = fscanf (FID,' % s '); D = fscanf (FID, '% x'); % close the file fclose (FID); disp (data); disp (s); disp (d );
 

From the output results, we find thatSpaces are ignored when fscanf reads data until you press Enter!

Disp:

The DISP function directly outputs the content in the MATLAB command window:

 
% Single string output: disp ('Hello world! '); % Output of different data types: num1 = 1; num2 = 2; disp ([num2str (num1),' + ', num2str (num2),' = ', num2str (num1 + num2)]);
 

Output:

Hello world!

1 + 2 = 3