|
|
Publications: IASPEI Software: Y2k Info |
|
W. H. K. Lee apologizes for the delay in completing these Web pages. Please note that IASPEI software is written and edited by volunteers. Your patience is greatly appreciated. |
The IASPEI PC Working Group found some Y2K problems in several of the programs published in Volume 1 and Volume 2, and has updated these programs for Y2K compliance. Registered users may download these updated programs for free. A username and a password are required for download, and users must agree to the License Agreement displayed on the screen before the download. As for Volumes 3-6, we do not think there are any serious Y2K problems as none of the programs in these volumes call the PC clock. All authors have been contacted, and they (except Anthony Lomax, the author of "SeisGram" in Volume 3) don't believe there are any serious Y2K problems with their software (SeisGram displays the year incorrectly after Y2K, but this problem, while annoying, does not affect any computation).
Registered users should receive a letter containing the username and password by October 15, 1999. If you have not registered your IASPEI Software Library volume(s), you should do so now by using the registration form included with the software volume. If you have registered, but have not received the letter by October 15, 1999, please contact Willie Lee by email to <whklee@ix.netcom.com>, or by fax at (650) 858-2599.
For data acquisition using IASPEI software, you also need "hardware" Y2K compliance. Users whose budget will not permit them to upgrade or replace their IBM-compatible PC hardware may wish to reset the PC clock with the DOS "date" command to 20 years earlier.
| IMPORTANT NOTE-All IASPEI software requires running the DOS operating system. Your PC may crash if you run the IASPEI software under the Microsoft Windows operating systems. |
Software and instructions for testing Y2K compliance for IBM-compatible PC hardware are available in our download area (see section V below for instructions on how to access the download area).
Six volumes of IASPEI Software Library volumes have been published in the past decade. Most of the IASPEI programs do not have any Y2K problems because there are either no date/time data involved or the date/time data are passive. However, there are several programs which use the time stamp of the PC clock that will give some annoying results. Typically, the last two digits of the year will become "00" in the year 2000. Still, this will not cause any of the programs in the IASPEI Software Library to crash when the PC clock enters the year 2000. In the following sections, we will comment only on programs that have Y2K problems that we are aware of. If you have run into Y2K problems on programs that we do not mention below, please contact Willie Lee at once by email at <whklee@ix.netcom.com>.
The data-acquisition software (MDETECT, XDETECT, XRTP, and XRTPDB) will not output data files with correct filenames when the PC clock enters the year 2000. As announced in 1994, the MDETECT and XDETECT programs are no longer supported, and users have been urged to switch to the XRTP program in the Second Edition of the IASPEI Software Volume 1. If you still prefer using MDETECT and XDETECT, please see section IV below.
To be Y2K compliant, users of the XRTP and XRTPDB programs must either
(1) add one line of specification to their input file, or
(2) download and use a revised XRTP (or XRTPDB) program.
Option (1) is simple. Add the following line to the required input file for the XRTP (or XRTPDB) program:
EventFilenameFormat= SSSSSSST;
This statement will change the default output file name from YYMMDDNN [year (two digits), month (two digits), day (two digits), and number (two characters)] to an eight-character filename which is derived from the time in seconds since 1970, and thus is Y2K compliant.
The Y2K compliant versions of XRTP and XRTPDB are available for download as XRTP228.EXE, and XRTPDBY2.EXE, respectively. They work exactly like the old programs, and the default output filename is in the YYMMDDNN format (with YY=00 for year 2000).
HYPO71PC will fail only under a very rare situation, i.e., if the arrival times are given in the early seconds of 00:00 of January 1, 2000, and the origin time is actually in the late seconds of 23:59 of December 31, 1999. In this case, please enter the arrival times with "991231" (for year, month, and day), "2359" (for hour and minute), and add 60 seconds to the arrival times. Please note that HYPO71PC only accepts the last two digit of the year, so "2000" will be represented by "00". However, the computation will not be affected, because times are relative to the year, month, day, hour, and minute entered in the input data. For users who wish to have a Y2K compliant version of HYPO71PC, please see section IV, Additional Information, below.
For the Y2K compliant version of "Earthquake Location Tools", please see section IV below.
For the Y2K compliant version of "Waveform Plotting Tools", please see section IV below.
The programs in Volumes 3 through Volume 6 do not call the PC clock for time, i.e., Date/time information, if any, is passive and is supplied by the users.
However, some programs may not interpret "00" as the year "2000". The result may be displaying the year incorrectly. For example, SeisGram in Volume 3 will display "1Jan19:0" instead of "1Jan2000". However, this error does not affect the computation. Anthony Lomax, the author of SeisGram, is now fixing this annoying problem, and we will post the Y2K version of SeisGram to this Web site as soon as possible.
Therefore, we do not think there are any serious Y2K problems, and this has been confirmed by the authors of Volumes 3 to 6. If any updating is necessary, we will inform users on this Web site.
"Earthquake Location Tools" in Volume 1, and "Waveform Plotting Tools" in Volume 2 are parts of the "PC-SUDS Utilities" written by Robert Banfill. Recently, the author has revised all his programs to be Y2K compliant. Utilities corresponding to those published in Volume 1 and Volume 2 are available for download by registered users.
The following information was received on April 16, 1999 from Tom Murray, U.S. Geological Survey, Cascades Volcano Observatory, 5400 MacArthur Blvd., Vancouver, WA 98661, USA. [email: tlmurray@usgs.gov; Phone: (360) 993-8933; Fax: (360) 993-8980]. Tom has kindly agreed to let us post it, so that any interested users of IASPEI Software Library may contact him.
"We made modifications to the PC-seis program used by AVO, CVO, VCAT, and various other volcano observatories so that they can work past the year 2000. The program will continue to use the yymmddxx format with the year correctly truncated to the last two digits. Therefore April 15, 2000 will be 000415. I realize that this is not Y2K compliant as there is the obvious century ambiguity. However, I decided not to implement the seconds from 1970 as you suggest as I found it to be too radical a change for most sites, requiring an interpreter of some sort to make sense of the filename. Realistically, most people's machines will fail and need replacing anyways within 5-10 years and at that time they can upgrade to a system that will provide strict Y2K compliance. In the meanwhile, this solution provides an easy fix for existing systems.
"We also modified HYPO71PC and recompiled it to produce a Y2K-compatible version we call HYPO1971. In this instance we followed Fred Klein and John Lahr's lead by adding a century flag in variable Test(14). The output summary lines then start with the 4-digit year (with the first two digits coming from Test(14), and the second 2 digits, as always, from the phase information). The rest of the summary line is the same and therefore all other fields are shifted to the right 2 places. When we compiled this as a 32-bit application, we also discovered that the Digital Visual Fortran compiler seems to take some of the calculations out to greater precision than the 16-bit compiler and some of the square root arguments became slightly negative, producing errors. We had to add a function (SafeSqrt) to check all SQRT calls for positive arguments. The summary output remained identical between versions.
"We also updated PC-QPLOT to incorporate Fred's changes to that program to read the new data formats and include 4-digit years on the plots.
"We will continue to run some tests and I feel confident that by mid-June the programs could be distributed to our users, though I think we are planning on an August-September release."
To access the IASPEI Software Y2k Download Area please click the link at the end of this section. You will be prompted for a username and password (all registered users of the relevant volumes of IASPEI software should have received a letter with these by October 15, 1999). After your username and password have been authenticated, a page will load with a form on which you must enter your name and email address and indicate that you have read and accept the software license. After clicking the button at the bottom of that page to submit the form you will be taken to the directory from which you can download.
There are 3 subdirectories with downloadable files. The first, "AcqY2k", contains two critical programs for data acquisition. The second directory, "PCSUDSy2k", are utilities to correct minor problems. The files in the third directory, "y2kTest" are for testing hardware for y2k compliance.
If you have further questions about IASPEI Software Y2k issues, please contact Willie Lee by email at <whklee@ix.netcom.com>, or by fax at (650) 858-2599.
Last Update: 02 November 2004