How to save the output of loop function with different names?

I created a for loop code which gives graphs as output. How can I save the graph seperately during each iteration?

[Stephen23]

https://www.mathworks.com/help/matlab/import_export/process-a-sequence-of-files.html

https://www.mathworks.com/help/matlab/ref/saveas.html

[Dyuman Joshi]

Use saveas

Answer 1

[KSSV]

for i = 1:10
    fname = strcat('plot_',num2str(i),'.png') ;
    plot(rand(1,10))
    saveas(gcf,fname)
end

Answer 2

[Image Analyst]

Use exportgraphics:

help exportgraphics

  EXPORTGRAPHICS  Save plot or graphics content to file
    EXPORTGRAPHICS(OBJ, FILESPEC) saves the specified graphics to a file.
    OBJ is the handle of any type of an axes, a figure, a chart that can 
    be a child of the figure, a tiled chart layout, or a container within 
    the figure. FILESPEC is a character vector or string scalar specifying
    the name of a file to create. It must include the extension, and can
    optionally include a full or relative path. EXPORTGRAPHICS supports 
    creating JPEG, PNG, and TIFF images, and EPS, PDF, and EMF vector
    formats (EMF is only supported on Windows).
 
    EXPORTGRAPHICS(___, OPTIONS) saves the graphics to the file, applying  
    the specified OPTIONS. OPTIONS is one or more of the following 
    name-value pairs.
 
    'ContentType', CONTENTTYPE  how to generate content in vector format files
    CONTENTTYPE can be one of the following values
    - 'vector' to generate vectorized (scalable) output 
    - 'image'  to generate rasterized output (embed image) 
    - 'auto'   allow MATLAB heuristic to decide
    The default value is 'auto'
 
    'Resolution', DPI  specifies output resolution for images. DPI must be
    a positive whole number. The default value is 150
  
    'BackgroundColor', COLORSPEC  specifies the color to use as the background 
    COLORSPEC can be one of the following values
    - a color name, such as 'red', or 'w'
    - an RGB triplet, such as [1 0 0] or [1 1 1]
    - a hexadecimal color code, such as '#FFF' or '#FFFFFF')
    - 'none' to use either a white or transparent background, depending on 
       what the output format supports 
    - 'current' to use the graphic's current background color
    The default value is 'white'
  
    'Colorspace', COLORSPACE  the color space to use when generating output
    COLORSPACE can be one of the following values
    - 'rgb'  generates RGB true color output
    - 'gray' generates grayscale output
    - 'cmyk' generates cyan, magenta, yellow, black output
    The default value is 'rgb'
 
    'Append', APPEND  specifies whether to append the output to an existing file or replace the content.
    APPEND can have a value of true or false.
    - true appends the output to an existing file
    - false replaces the content in an existing file
    The default value is false
 
    Example: Export a plot to a pdf file 
       plot(rand(3)); 
       exportgraphics(gca, 'results.pdf'); 
 
    Example: Export a plot to a pdf file and ensure output is vectorized/scalable 
       plot(rand(3)); 
       exportgraphics(gca, 'results.pdf', 'ContentType', 'vector');
 
    Example: Export a plot as an image to a pdf file 
       plot(rand(3)); 
       exportgraphics(gca, 'results.pdf', 'ContentType', 'image');
 
    Example: Export a plot and append to an existing pdf file
       plot(rand(3)); 
       exportgraphics(gca, 'results.pdf', 'Append', true);
 
    Example: Export a specific plot from the figure
       fig = figure; 
       ax1 = subplot(2,1,1); bar(magic(4));
       ax2 = subplot(2,1,2); plot(rand(4));
       exportgraphics(ax2, 'results.png'); 
 
    Example: Export all plots from figure to an image file at 300DPI
       subplot(2,1,1); bar(magic(4));
       subplot(2,1,2); plot(rand(4));
       exportgraphics(gcf, 'results.png', 'Resolution', 300); 
 
    Example: Export a plot to an image file with a red background 
       plot(rand(3)); 
       exportgraphics(gca, 'results.png', 'BackgroundColor', [1 0 0]);
  
    Example: Export a plot to a grayscale image file  
       plot(rand(3)); 
       exportgraphics(gca, 'results.png', 'Colorspace', 'gray');
  
    See also COPYGRAPHICS, EXPORTAPP

    Documentation for exportgraphics
       doc exportgraphics

Sample code snippet. Adapt as needed:

folder = pwd; % or 'C;\wherever you want'
for k = 1 : 5
    % Create output filename.
    baseFileName = sprintf('Plot %2.2d.png', k);
    fullFilename = fullfile(folder, baseFileName);
    % Make up your graphs however you want.
    plot(rand(1, 10));
    xlabel('x');
    ylabel('y');
    % Save the current axes to disk with the filename we just created.
    exportgraphics(gca, fullFileNme);
end

Answer 3

[sushma swaraj]

Hi,

To save each graph separately during each iteration of a for loop in MATLAB, you can use the saveas function. Here's an example of how you can modify your code to save the graphs:

for i = 1:N
    % Add your code to generate the graph
    
    filename = sprintf('graph_%d.png', i);
    saveas(gcf, filename);
end

In this example, the for loop iterates N times. Inside the loop, you generate the graph using your code.After generating the graph, you can save it using the saveas function. The gcf command retrieves the handle of the current figure.

Hope it works!