About the data formats for LHC Optics tables

The formats are described in order of decreasing usefulness.  In all cases the values of optical functions are given at the ends of the elements (if you are standing upright inside the ring looking at an element, its end is on the right).  In certain cases (older versions of the optics) values are given at the centres of the elements. 

Structured Spreadsheets

As these are the richest and probably most useful of the table formats, there is a separate page providing tips on how to use these files.

CSV files

The CSV (Comma-Separated-Value) format is a plain text format that is widely used and can be opened directly by most spreadsheet and database applications.  The CSV files in this Web are exported from the Madtomma environment and contain the same additional information as the mfs expressions although their structure is less clearly defined.

The Madtomma packages are used to add the data and make the conversions.

TFS tables

These are the raw plain text tables as they come from MAD. The idea behind them is that of a Self-Describing Data Set, invented for data in the LEP Control System in the late 1980s (a later implementation of the same idea is called SDDS).   The Table File System (TFS) format  is defined in the MAD Users' Guide.  The Madtomma packages provide a complete object-oriented interface to the data in these tables by converting them to Mathematica expressions with the head mfs. 

The files consist of a header section containing a number of named quantities such as the date (descriptor "DATE") the file was generated or the vertical tune (descriptor "QY") of the machine.  The "body" of the file consists of  a number of number of named columns giving attributes (e.g. NAME, K1L) and optical functions values (e.g. BETX) at each element.

The mfs expressions created in Mathematica contain additional information, not supplied by MAD, in the header sections (e.g. the quantity "Brho" used to convert normalised magnet strengths to field gradients or the origin of the data).   This information is added to the CSV and Structured Spreadsheet format versions of the tables.

Plain HTML tables

These show the data in the CSV files in an HTML table format for the convenience of users who cannot use the Structured Spreadsheet format. Some Web browsers (e.g. certain versions of Netscape Navigator) are known to be very slow to display these files. 

This Web, the MAD input files and all the data  were created automatically by the Mathematica notebook LHCOpticsWebPages.nb, based on the Madtomma packages.
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