Information on types of files available on N. C. Phillips' web pages

This page describes the formats of the non html files provided through the home pages for my courses and my research. Documents originally written in TeX are normally provided in two formats: pdf and AMSLaTeX (or other species of TeX) source code. Sometimes ps (Postscript) and dvi files may also be provided. A few files are plain text, or gif or jpg (scanned).

Warning: At least one person who printed some of my pdf files somewhere at the University of Oregon found that certain mathematical symbols did not print. This seriously damaged the meaning of some of the mathematics. I do not know what caused the problem; the original pdf file was afterwards verified to display correctly on my Mac. (This happened during the Fall quarter 1998.)

Here are some comments on the different formats.

pdf (Adobe Acrobat)

This version is the most likely to be properly displayed by most browsers. (However, see the warning above.)

ps (Postscript)

This is the format used to send files to Postscript printers (very common). It comes out sharply on my machines, but most browsers probably won't display it. Moreover, the file size is huge (generally about five times the size of the pdf file, the next biggest).

dvi (device independent)

This kind of file is generated by TeX processing programs. Most browsers probably won't display it. The file are much smaller than the ps files. If the file is supposed to contain pictures, there is one other major disadvantage: the pictures must be downloaded separately. A display made directly from the file on my web site will have blank space (actually, probably black) wherever a picture belongs. The files needed for the pictures can usually be found in the same directory as the dvi file (usually not the directory containing the document that links to the dvi file), and have names ending in .eps. (This problem is unlikely to occur for files related to my research or to graduate courses.)

AMSLaTeX (or other species of TeX) source code

These are ASCII files used as input to the mathematical word processing program AMSLaTeX. Occasionally they are for other variants of TeX, such as plain TeX, AMSTeX, or LaTeX. The first line of the file usually indicates which species of TeX to use. TeX (Wikipedia entry) is the only program I know which does a reasonable job of typesetting mathematical formulas. (Free versions are available for all common operating systems.) You need the TeX program to make something reasonable out of these files, although if you are familiar with TeX you might be able to understand the raw files. If the file is supposed to contain pictures, the same problem occurs as with the dvi files (see above), although the outcome is usually an error message rather than a blank space in the file.

Most browsers will either download the file or display the source code.

Plain text (ASCII)

If this is the file type, usually no other version is provided. My text files are designed for a fixed width font, and the spacing may come out strangely if a variable width font is used.

gif or jpg

These are pictures, usually created by scanning something when I could not create useful pictures with computer software.

This page maintained by N. Christopher Phillips, email.

Last significant change 13 December 2007.