Editing S (programming language) (section)

==="New S"===
The first version of [[S-PLUS]] was released by Statistical Sciences, Inc. in 1988. S-PLUS was later sold to [[TIBCO Software]].<ref name=":1" /> By this time, many changes were made to S and the syntax of the language with the release of S3.<ref name=":3" /> ''The New S Language''<ref>{{cite book |last=Becker |first=R.A. |author2=Chambers, J.M. |author3=Wilks, A.R.  |title=The New S Language: A Programming Environment for Data Analysis and Graphics |year=1988 |publisher=Wadsworth & Brooks/Cole |location=Pacific Grove, CA, USA |isbn=0-534-09192-X }}</ref> (known as the 'Blue Book') was published to introduce the new features, such as the transition from ''macros'' to ''functions'' and how functions can be passed to other functions (such as <code>apply</code>). Many other changes to the S language were to extend the concept of "objects", and to make the syntax more consistent (and strict). However, many users found the transition to ''New S'' difficult, since their macros needed to be rewritten. Many other changes to S took hold, such as the use of [[X Window System|X11]] and [[PostScript]] graphics devices, rewriting many internal functions from Fortran to C, and the use of [[double precision]] (only) arithmetic. The ''New S'' language is very similar to that used in modern versions of [[S-plus|S-PLUS]] and [[R (programming language)|R]].

The graphical user interface of S was also updated interactive graphical features after integration with [[Axum (programming language)|Axum]].<ref name=":1" />

''Statistical Models in S''<ref>{{cite book |last=Chambers |first=J.M. |author2=Hastie, T.J.  |title=Statistical Models in S |year=1991 |publisher=Wadsworth & Brooks/Cole |location=Pacific Grove, CA, USA |isbn=0-412-05291-1 |page=624}}</ref> (known as the 'White Book') was published in 1991, introducing Wilkinson-Rogers formula notation<ref>{{cite journal |last=Wilkinson |first=G.N. |author2=Rogers, C.E.  |year=1973 |title=Symbolic description of factorial models for analysis of variance |journal=Applied Statistics |volume=22 |issue=3 |pages=392–399|doi=10.2307/2346786 |jstor=2346786 }}</ref> (using the <code>~</code> operator) for defining statistical models, data frame objects, and modifications to the use of object [[Method (computer science)|methods]] and [[Class (computer science)|classes]].