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Fortran, Fortran

Said creator John Backus during a 1979 interview with Think, the IBM employee magazine, "Much of my work has come from being lazy. I didn't like writing programs, and so, when I was working on the IBM 701 (an early computer), writing programs for computing missile trajectories, I started work on a programming system to make it easier to write programs." Fortran creator John Backus dies - Gadgets - MSNBC.com The language was widely adopted by scientists for writing numerically intensive programs, which encouraged compiler writers to produce compilers that could generate faster and more efficient code.

This is not true, the 704 branch instructions all contained only one destination address (e.g., TZE Transfer AC Zero, TNZ Transfer AC Not Zero, TPL Transfer AC Plus, TMI Transfer AC Minus). The machine (and its successors in the 700/7000 series) did have a three-way skip instruction (CAS Compare AC with Storage), which was probably the origin of this belief, but using this instruction to implement the IF would consume 4 instruction words, require the constant Zero in a word of storage, and take 3 machine cycles to execute; using the Transfer instructions to implement the IF could be done in 1 to 3 instruction words, required no constants in storage, and take 1 to 3 machine cycles to execute. An optimizing compiler like FORTRAN would most likely select the more compact and usually faster Transfers instead of the Compare (use of Transfers also allowed the FREQUENCY statement to optimize IF s, which could not be done using the Compare). Also the Compare considered 0 and +0 to be different values while the Transfer Zero and Transfer Not Zero considered them to be the same.

A comprehensive summary of the new features of Fortran 2003 is available at the Fortran Working Group (WG5) official Web site.

Information on Fortran standardization in general and progress on Fortran 2008 is at http://j3-fortran.org.

It is intended to be a fairly comprehensive overview of the Fortran language as currently implemented (essentially, Fortran 95); full details may be found in any Fortran 95 textbook. Only those features widely used in new programs are described, as many of the historic features are no longer used in modern programs (although most have been retained in the language in order to maintain backward compatibility).

J. Perlis, J. W. Smith, and H. R. Van Zoeren, Computation Center,Carnegie Institute of Technology in the late 1950s.The following comment appears in the IBMReference Manual ("FOR TRANSIT Automatic Coding System" C28-4038, Copyright 1957, 1959 by IBM): The FORTRAN system was designed for a more complex machine than the 650, and consequently some of the 32 statements found in the FORTRAN Programmer's Reference Manual are not acceptable to the FOR TRANSIT system.

Source: Wikipedia > Fortran