No, you do not need to use LSL if you use LP. LP has its own input format (although it is very similar to LSL's input format). So, many users of LP simply bypass LSL, and use LP exclusively. On the other hand, using LSL as an input format to LP has the following advantages. The LSL checker automatically generates proof management commands (scripting and logging) for LP, and helps organize theories and conjectures into files. See section 3.10 How do I use LP to check my LSL traits?.

The following makefile shows one way to use the Unix command make to help check LSL traits. It relies on properties of the Bourne shell under Unix and standard Unix make, so it would have to be adjusted to work on other systems. (Also, if you cut and paste this makefile, be sure to change the leading blanks to tab characters on the rule lines.) SHELL = /bin/sh LSL = lsl LSLFLAGS = .SUFFIXES: .lsl .lsl-ckd .lp .lsl.lsl-ckd: $(LSL) $(LSLFLAGS) $< 2>&1 | tee $ .lsl.

Yes, there actually is a version of "spiderweb" specialized for use with LSL. If you are really a fan of such fancy systems, you can find it by using the literate programming library's URL. http://www.desy.de/user/projects/LitProg.html However, we have found that using the "noweb" system is much easier for most people, and nearly as good. You can get noweb from the literate programming library (see above), or directly from the following URL. http://www.eecs.harvard.edu/~nr/noweb/intro.

The LSL checker, when used with the '-lp' switch on a file named 'Foo.lsl', in general produces three files: 'Foo_Axioms.lp', 'Foo_Checks.lp', and 'Foo_Theorems.lp'. Each of these files is in LP input format, hence the suffix '.lp'. The file 'Foo_Axioms.lp' contains a translation of the trait in 'Foo.lsl', minus the implies section. It is "executed" by LP when LP is executing the translation of some other LSL trait that includes Foo. The file 'Foo_Checks.

No, you don't always have to write an LSL trait to specify something in a BISL, it just seems that way. Seriously, you don't have to write a trait in the following circumstances. You are specifying a procedure and all of the mathematical vocabulary needed is available in existing traits. These traits may come from a handbook (see section 2.23 Where can I find handbooks of LSL traits?), or they may be built-in to your BISL.

Although one cannot list both unknown and hmm in the same converts clause, one could add another converts clause to the trait ConvertsTrait, stating that unknown is converted, relative to the other operators, which in that case include hmm.

You can get the MIT releases of the LSL checker using the world-wide web, starting at the following URL. http://www.sds.lcs.mit.edu/spd/larch/lsl.html You can also get the MIT release by anonymous ftp from the following URL. ftp://ftp.sds.lcs.mit.edu/pub/Larch/LSL/ Iowa State, the Larch/C++ group has made available later beta releases of the LSL checker that fix problems with its profligate use of space. You can get the sources for Unix and Windows 95 executables from the following URL.

Yes. Name reservations are now “generic” and can be used to form any type of filing entity.

No, cddlib is already linked with the mex interface, so there is no need to download it separately, unless you plan to re-compile the interface.

Currently, LP only runs on Unix machines. You can get an implementation of LP using the world-wide web, starting at the following URL. http://www.sds.lcs.mit.edu/spd/larch/LP/news/distribution.html You can also get an implementation by anonymous ftp from the following URL. ftp://ftp.sds.lcs.mit.edu/pub/Larch/LP/ See section 2.

If you are running LP under Unix, the Unix "quit" character (usually C-g, that's control-g) will interrupt LP's execution. See section 3.6 Can I change the erase character in LP?, for other characters that aid in editing interactive input to LP. See section 3.20 How can I develop a proof that I can replay later?, for a way to avoid tedium and much direct interaction with LP.

We recommend checking your local codes first. Expect to use at least a one- hundred-pound cylinder. Using a twenty-pound cylinder may cause problems during extreme cold conditions., i.e., freezing regulator, frost on tank, nuisance shut downs.

To showcase your talents and abilities. In GLC, you can search by name and pull out the lesson plans of teachers whose lessons and activities work for your students.

I do believe in having a second tank around. During summer months I keep a full one in the garage to swap out when the one on the pop-up gets low. During the winter I carry the second tank while camping because it can get mighty cold if you run out of gas and it's 40 outside. It is possible to get an automatic changeover regulator which will switch to a second tank when the first one is empty.

The main difference between LSL and a Larch BISL is that in LSL one specifies mathematical theories of the operators that are used in the pre- and postcondition specifications of a Larch BISL. Thus LSL is used to specify mathematical models and auxiliary functions, and the a Larch BISL is used to specify program modules that are to be implemented in some particular programming language.

The Larch Shared Language (LSL) (see [Guttag-Horning93], Chapter 4, and [Guttag-Horning-Modet90]) is a language for specifying mathematical theories. LSL is a kind of equational algebraic specification language [Guttag75] [Guttag-Horning78] [Goguen-Thatcher-Wagner78] [Ehrig-Mahr85] [Futatsugi-etal85] [Mosses96] [Loeckx-Ehrich-Wolf96]. That is, specifications in LSL mainly consist of first-order equations between terms.

Besides this FAQ, the best place to look is probably your own computer system. You should have a manual page for the LSL checker, if it's installed on your system. Try the Unix command man lsl to see it. You should also look for a directory (such as '/usr/larch/LSL') where the installation of LSL is found. In that directory, you will find a subdirectory 'Doc', where there is some documentation on the checker. See section 2.

The sections of an LSL trait are determined by the LSL grammar [Guttag-Horning-Modet90]. (See section 2.3 Where can I get a checker for LSL?, for a more recent grammar, which is found in the file 'Doc/lsl3_1.y', for version 3.1, and 'Doc/lsl3_2.y', for version 3.2.

LSL trait denotes a theory, which is a collection of true formulas (of sort Bool). This theory contains "the trait's assertions, the conventional axioms of first-order logic, everything that follows from them, and nothing else" (see [Guttag-Horning93], p. 37). For a brief introduction to these ideas, see Chapter 2 of [Guttag-Horning93]; for general background on equational logic, see [Ehrig-Mahr85] or [Loeckx-Ehrich-Wolf96].

Technically, no; all functions specified in LSL are total (see section 2.14 What is the meaning of an LSL specification?). Thus every operator specified in LSL takes on some value for every combination of arguments. What you can do is to underspecify such an operator, by not specifying what its value is on all arguments. For example, the operator head in the handbook trait List (see [Guttag-Horning93], p. 173) is underspecified in this sense, because no value is specified for head(empty).

No, you don't have to specify everything completely in LSL. It's a good idea, in fact, to only specify the aspects that are important for what you are doing. For example, if you want to reason about graph data structures, it's best to not (at first, anyway) try to specify the theory of graphs in great detail. Put in what you want, and go with that. (This won't hurt anything, because whatever you need to prove you'll be forced to add eventually.

According to Guaspari (posting to the larch-interest mailing list, on March 8, 1995), "the commonest 'purely mathematical' mistakes" in trait definitions occur when one uses structural induction "over constructors that don't freely generate a sort". To understand this, consider his example, which includes the handbook trait Set (see [Guttag-Horning93], page 167).

The first tip helps you write down an algebraic specification of a sort that is intended to be used as an abstract data type (see [Guttag-Horning78], Section 3.4, and [Guttag-Horning93], Section 4.9). The idea is to divide the set of operators of your sort into generators and observers. A constructor returns your sort, while an observer takes your sort in at least one argument and returns some more primitive sort (such as Bool). The tip (quoted from [Guttag-Horning93], p.

The most commonly-used handbook of LSL traits is Guttag and Horning's handbook ([Guttag-Horning93], Appendix A). This can be obtained by anonymous ftp with the LSL checker (see section 2.3 Where can I get a checker for LSL?). A hypertext version is on-line in http://www.research.digital.com/SRC/larch/toc.html A general resource for all known handbooks that are publically available is found on the world-wide web, at the following URL. http://www.cs.iastate.edu/~leavens/Handbooks.

You can get a LaTeX style file, 'larch.sty', and a macro file defining a bunch of mathematical symbols, 'larchmath.tex', by anonymous ftp from the following URL. ftp://ftp.cs.iastate.edu/pub/larch/tex The documentation for 'larch.sty' says that it is to be used with LaTeX 2.09. However, it can be used with LaTeX2e. To do so, put the following lines at the start of your LaTeX input.

All Mendota models can be converted to burn LP gas. Make sure to notify your certified Mendota dealer prior to ordering if your home requires LP gas appliances.

We have found linprog very unreliable for the kind of problems the toolbox is solving. For instance, very often you will get an infeasible solution from linprog for a given linear program, while the other solvers are able to return a correct solution. Besides this fact, linprog is also very slow comparing to other available solvers.

We require using at least a one hundred-Gallon or larger tank. Do not use a twenty-pound cylinder. Undersized tanks are known to cause problems during extreme cold conditions

The LGPL is as clear as fog on what is allowed, what is not, and what is commercial.