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Size of Output Files

When you print a figure rendered with painter's algorithm, the resolution has little effect on the size of the output file or the amount of memory needed for printing. Therefore, the default resolution is quite high (864 dpi for MATLAB's built-in PostScript drivers).

When you print a figure rendered using z-buffer, certain factors directly influence the size of the output file or amount of memory needed for printing:

These relationships exist because Z-buffer figures are rendered as bitmaps, and the number of pixels in a bitmap is a function of the resolution and of the size of the graphic. For example, if a figure is 2 inches by 3 inches, it will consist of 60,000 pixels at 100 dpi. Increasing either the resolution or the size increases the number of pixels proportionately. For example:

Note that the size of the actual output is what matters, not the size on the screen (although, if PaperPositionMode is set to auto, the size on screen and on paper are the same).

For figures rendered using Z-buffer, the default resolution is 150 dpi. To set the resolution to a different value, use the -r option. The syntax is:

number is the number of dots per inch. For example, to specify a resolution of 100 dpi:

To specify printing at screen resolution, set number to 0 (zero):

In addition to the figure size and resolution, the choice of color or black and white also affects the size of the file, because the amount of information stored for each pixel is larger for color than for black and white. Color files are three times as large as black and white files, so be sure to use a black and white driver unless you want to print to a color device.

Because of these issues, you must make trade-offs between resolution, size, color, and printing resources, when printing a figure rendered using Z-buffer. For example, you can specify any resolution, but you may find at higher resolutions the resulting files are too big and require too much memory to print. However, you are likely to find that much lower resolutions produce acceptable results.


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