A TASTE OF QUAIL

Quail is both a command line programming environment and a display-oriented environment for carrying out quantitative analysis. In Quail, the two approaches are freely mixed. One of the principal research interests in Quail is the integration of the two.

Here we provide access to some information on both.

• Typed expressions are accepted, evaluated, and the answers printed in lisp's `top-level' read-evaluate-print loop as demonstrated below:
  
  

  Bold face type is typed by the user. The user types an expression which is read by this toplevel loop and evaluated according to the nesting of the parentheses and in left to right fashion (with the exception of the leftmost characters which represent the operator). The result of the evaluation is then printed.

  Some notes:

  1. This is a pretty rudimentary example which uses the environment as a calculator.
  2. At least four different types of numbers are demonstrated: integers (actually fixnums here), rationals, floating-point numbers, and complex numbers. Quail actually extends the number system further to accommodate IEEE arithmetic operations.
  3. Some symbols (like pi ) are built in constants.
  4. Symbols like x (or any other sequence of contiguous characters) can be assigned a value.
  5. The Quail assignment operator <- , a left arrow, returns no value.
  6. There are hundreds of functions built into Common Lisp and also its data analytic extension Quail. Here we see arithmetical operators and the square root function sqrt . Here are some other arithmetic operators for arrays in Quail.
• Quail (and Common Lisp) can be extended by defining new functions, generic functions and methods, and macros. Here we very briefly show a function written in common lisp using defun and illustrate how this is done interactively, and then immediately used.

In Quail, there are a series of example files which can be used interactively (in Quail) to explore some of the features that Quail has added to Common Lisp. (These come as part of the Quail software that can be down loaded.)

What appears here is a somewhat recent copy of these files. They are organized by topical directories. Note however that no serious attempt has been made in this html document to keep the example files found here either up to date or complete.

Movies that are recorded here are recorded in Quicktime. If your browser doesn't have a Quicktime plugin, you might want to visit the Quicktime site. Any choppiness in the images is due to the low rate (5 per minute) used to capture the interactions.

The tidbits

1. Quail provides a good deal of information including a help system and collection of example files showing the programmatic use of Quail's extensions to Common Lisp. Much of this information is accessible through an ever-present Quail menu. This menu also provides the user with access to system datasets and control over the default appearence of the Quail environment.
2. While a type in interface is available and typically heavily used, Quail provides a system level menu so that users can conveniently access plots. Here the plots menu is shown.
3. Basic mouse interaction on plots in Quail. Here the basic suite of interactions in Quail are described. A simple scatterplot is used to illustrate these.
4. The scatterplot . This is the same as above but feel free to skip over the familiar.
5. Three dimensional scatterplots.