Concepts of programming languages,10th. Chapter 2, Assignment 2,

Lecturer: Tri Djoko Wahjono, ir.,M.Sc.

1. In what year was Plankalkül designed? In what year was that design published?

Answer: Plankalkul was designed in 1942 - 1945,designed in 1972.

2. What two common data structures were included in Plankalkül?

Answer: Array and Record

3. How were the pseudo codes of the early 1950s implemented?

Answer: They were implemented through pure interpreter.

4. Speedcoding was invented to overcome two significant shortcomings of the computer hardware of the early 1950s. What were they?

Answer: Non-connotative names, absolute addressing (Also: floating-point arithmetic, automatic incrementing of address register).

5. Why was the slowness of interpretation of programs acceptable in the early 1950s?

Answer: It is because the lack of floating point hardware

Problem Set:

1. What features of Plankalkül do you think would have had the greatest influence on Frotran 0 if the Fortran designer had been familiar with Plankalkül ?

The ability to pass subprograms as parameter for a subprogram. Because this, in my opinion would widen the design capability of a program written with Java.

2. Determine the capabilities of Backus’s 701 Speedcoding system, and compare them with those of a contemporary programmable hand calculator.

Short Code consists of coded version of mathematical expression that was to be evaluated. Short code can be used to code many equations such as power, square roots, addition, subtraction, division but there is no multiplication code. Short code was able to be implemented into UNIVAC I computer. In the other hand contemporary programmable calculator was able to do multiplication with its embedded programming language. So with the contemporary calculator people can solve arithmetic problem easier than using the Short Code but it is more difficult to do further improvement to the programmable hand calculator than to the Sort Code.

3. Write a short history of the A-0,A-1,and A-2 systems designed by Grace Hopper and her associates.

The A-0 system was written by Grace Hopper in 1951 and 1952 for the UNIVAC I, was the first compiler ever developed for an electronic computer. The A-0 functioned more as a loader or linker than the modern notion of a compiler The A-0 system was followed by the A-1, A-2, A-3 (released as ARITH-MATIC), AT-3 (released as MATH-MATIC) and B-0 (released as FLOW-MATIC).

4. As a research project, compare the facilities of Fortran 0 with those of the Laning and Zierler system.

Laning and Zierler system was one of the first operating algebraic compiler that capable of the accepting mathematical formula in algrebraic notation and producing equivalent machine codes. While, Fortran 0 capable to accomodate scientific and engineering applications while also can do what Laning and Zierler system do plus engineering application.

5. Which of the three original goals of the ALGOL design committee, in your opinion, was most difficult to achieve at that  time?

In my opinion the most difficult to achieve from the three original goals of the ALGOL design committee are providing the efficiency of hand-coded programs. I think this is the most difficult to achieve, because there are a lot of modifications and a lot of things to add and to fix in order to make an efficient code program.