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The authors provide a brief history of the firm now called East View Information Services. From its beginning in 1989 as a sole-proprietorship company, it has grown from microfilming the back file of a single Soviet journal to being a subscription agent, book vendor, database aggregator, provider of maps and other geospatial information, and more—from Slavic countries, East Asia, the Middle East, and elsewhere.

Many language implementations, like C++ and Java, check the types of values and operations to be sure each operation is supported for the types of its operands. An important feature of Standard ML is the type inference system which is somewhat like the type checkers of C++ and Java, but a bit more powerful. A type checker checks the types written by the programmer to be sure each type declaration is consistent with the operations being performed, values being passed to functions, and the values being returned. Compilers for Java and C++ even infer the types of some expressions when polymorphic operators are used. For instance, the addition operator has multiple result types depending on the types of its operands.

The ML in the name Standard ML stands for meta-language. SML was designed as a language for describing languages when it was used as part of the Logic for Computable Functions (LCF) system [9]. Two tools were designed to work with Standard ML for language implementation, ML-lex and ML-yacc. The pattern matching, ease of defining recursive datatypes, the functional nature of the language along with these two tools make Standard ML an excellent language choice for implementing interpreters and compilers.

In November, 2004 the National Geospatial-Intelligence Agency (NGA) announced its intention to withdraw essentially all of its aeronautical chart and related digital data publications from public distribution. Citing multiple concerns (potential use by terrorists, potential threats to the integrity of its own data, and commercial/copyright issues), NGA's proposed withdrawal would have removed huge volumes of traditionally open data from public access and established ominous precedents in the post-9/11 environment. Map libraries of all kinds would have been affected correspondingly. The paper seeks to explore each stated rationale by NGA, and also seeks to explain all NGA product series, including some rather arcane digital products, that were at stake for withdrawal.

When using formal methods to generate compilers it is desirable for all levels of the compiler to be formally specified. Typically, register allocation has been thought to be equivalent to graph coloring. Since graph coloring is NP-Complete most algorithms for register allocation have been ad-hoc. This paper presents a framework for register allocation that has been formally verified using an inductive theorem prover.

Access to global geospatial data, and the way these data are being used, has changed dramatically in the past decade. This is true for a variety of reasons, many of them not readily apparent. This article will explore some of the essential changes in this sphere since the early 1990s, as seen from the perspective of a commercial distributor and service bureau involved with international maps and related data.

This is the sample drawing application from the first chapter. It illustrates the use of the tkinter library including many widgets and mouse handling. This program can be downloaded from the text’s website.

This documentation was generated from the Python documentation available by typing from turtle import * help (TurtleScreen) in the Python shell.

In the last chapter we studied sequences which are used to keep track of lists of things where duplicate values are allowed. For instance, there can be two sixes in a sequence or list of integers. In this chapter we look at sets where duplicate values are not allowed. After examining sets we’ll move on to talk about maps. Maps may also be called dictionaries or hash tables.The term hash table actually suggests an implementation of a set or map. The primary focus of this chapter is in understanding hashing. Hashing is a very important concept in Computer Science because it is a very efficient method of searching for a value. To begin the chapter we’ll motivate our interest in hashing, then we’ll develop a hashing algorithm for finding values in a set. We’ll also apply hashing to the building of sets and maps. Then we’ll look at an important technique that uses hashing called memoization and we’ll apply that technique to a couple of problems.

This documentation was generated from the Python documentation available by typing from turtle import * help (Turtle) in the Python shell.

This first chapter introduces Python to readers that have never programmed in Python before. It also provides instructions for installing Python on your computer. The Wing Integrated Development Environment (IDE) is recommended for students learning to program. Wing IDE 101 is the free version of the IDE for educational use. The chapter goes on to introduce classes, objects, and object-oriented programming by developing a drawing application using the Tkinter graphical user interface library. An understanding of object-oriented programming concepts presented in this chapter is necessary before reading the rest of the text. The PyList datatype presented in this chapter is also used in subsequent chapters including Chap. 2. Even if the reader has worked through an introductory text or has a basic understanding of Python, there are concepts from this first chapter that are used throughout the text.

This documentation was generated from the Python documentation available by typing help(list) in the Python shell.

In Chap. 6 binary search trees were defined along with a recursive insert algorithm. The discussion of binary search trees pointed out they have problems in some cases. Binary search trees can become unbalanced, actually quite often. When a tree is unbalanced the complexity of insert, delete, and lookup operations can get as bad as \(\Theta (n)\). This problem with unbalanced binary search trees was the motivation for the development of height-balanced AVL trees by G.M. Adelson-Velskii and E.M. Landis, two Soviet computer scientists, in 1962. AVL trees were named for these two inventors. Their paper on AVL trees [AVL62] described the first algorithm for maintaining balanced binary search trees. The chapter goes on to discuss Splay Trees as another example of balanced binary search trees.

This documentation was generated from the Python documentation available by typing help(dict) in the Python shell.

This documentation was generated from the Python documentation available by typing help(int) in the Python shell.

This documentation was generated from the Python documentation available by typing help(float) in the Python shell.

This documentation was generated from the Python documentation available by typing help(str) in the Python shell.