**Plankalkül** is a** programming** language , designed from 1942 to 1946 by the German Konrad Zuse . At the time, Zuse made no scientific communication on this subject, for various reasons: the Second World War was raging, and he devoted all his efforts to the design and commercialization of his computer, the Zuse 3 .

The first publication mentioning Plankalkül dates from 1948 . In 1975 , it was described and implemented on the occasion of J. Hohmann’s thesis. The first compiler, proposed by the Free University of Berlin , was completed in 2000 , five years after the death of Zuse.

## Description

According to Zuse, Plankalkül is the first language of high level .

This language, however, had the same unfortunate fate as its creator: thus it was extremely innovative, but outside the mainstream, global, development of computer science. He therefore remained largely unknown.

This language presents a rare, if not unique, innovation for a computer language: programs are written in two dimensions in the same way as algebraic notation. It is therefore closer to the traditions of the plan and the formula than to those of prose and narrative.

For these reasons, some even bring him closer to the object-oriented languages of which he is an ancestor, at an intermediate level between them and classical algebra.

## Example

The program below calculates the maximum of three variables by calling the *max* function :

P1 max3 (V0 [: 8.0], V1 [: 8.0], V2 [: 8.0]) => R0 [: 8.0] Max (V0 [: 8.0], V1 [: 8.0]) => Z1 [: 8.0] Max (Z1 [: 8.0], V2 [: 8.0]) => R0 [: 8.0] END P2 max (V0 [: 8.0], V1 [: 8.0]) => R0 [: 8.0] V0 [: 8.0] => Z1 [: 8.0] (Z1 [8.0]) V1 [8.0] => Z1 [8.0] Z1 [8.0] => R0 [8.0] END

## References

- Zuse, Konrad (1943), “Ansätze einer Theory of the allgemeinen Rechnens unter besonderer Berücksichtigung des Aussagenkalküls und Dessen Anwendung auf Relaischaltungen”, (ie
*Inception of a universal theory of computation with special consideration of the propositional calculus and its application to relay circuits*. Unpublished manuscript, Zuse Papers 045/018. - Zuse, Konrad (1948/49). “Über den allgemeinen Plankalkül als Mittel zur Formulierung schematisch-kombinativer Aufgaben”. Arch. Math. 1, p. 441-449, 1948/49.
- Zuse, Konrad (1972).”Der Plankalkül”.Gesellschaft für Mathematik und Datenverarbeitung.Nr. 63, BMBW – GMD – 63, 1972.
- Giloi, Wolfgang, K. (1997). “Konrad Zuse’s Plankalkül: The First High-Level” non von Neumann “Programming Language”. IEEE Annals of the History of Computing, vol. 19, no. 2, p. 17-24, April-June, 1997. (abstract) [ archive ]