A production or production rule in computer science is a rewrite rule specifying a symbol substitution that can be recursively performed to generate new symbol sequences. A finite set of productions is the main component in the specification of a formal grammar (specifically a generative grammar). The other components are a finite set of nonterminal symbols, a finite set (known as an alphabet) of terminal symbols that is disjoint from and a distinguished symbol that is the start symbol.
In an unrestricted grammar, a production is of the form where and are arbitrary strings of terminals and nonterminals however may not be the empty string. If is the empty string, this is denoted by the symbol , or (rather than leave the right-hand side blank). So productions are of the form:
The other types of formal grammar in the Chomsky hierarchy impose additional restrictions on what constitutes a production. Notably in a context-free grammar, the left-hand side of a production must be a single nonterminal symbol. So productions are of the form:
A record producer (or music producer) has a very broad role in overseeing and managing the recording (i.e. "production") of a band or performer's music. A producer has many roles that may include, but are not limited to, gathering ideas for the project, selecting songs and/or session musicians, proposing changes to the song arrangements, coaching the artist and musicians in the studio, controlling the recording sessions, and supervising the entire process through audio mixing (recorded music) and, in some cases, to the audio mastering stage. Producers also often take on a wider entrepreneurial role, with responsibility for the budget, schedules, contracts, and negotiations.
In the 2010s, the recording industry has two kinds of producers with different roles: executive producer and music producer. Executive producers oversee project finances while music producers oversee the creation of music.
A music producer can, in some cases, be compared to a film director, with noted practitioner Phil Ek describing his role as "the person who creatively guides or directs the process of making a record, like a director would a movie. The audio engineering [person] would be more the cameraman of the movie." Indeed, in Bollywood music, the designation actually is music director. The music producer's job is to create, shape, and mold a piece of music. The scope of responsibility may be one or two songs or an artist's entire album– in which case the producer will typically develop an overall vision for the album and how the various songs may interrelate.
Sol Invictus is an Englishneofolk and neoclassical group fronted by Tony Wakeford. Wakeford has been the sole constant member of the group since its inception, although numerous musicians have contributed and collaborated with Wakeford under the Sol Invictus moniker over the years.
After disbanding his controversial project Above the Ruins, Wakeford returned to the music scene with Sol Invictus in 1987. Since then Sol Invictus has had many musician contributions, including Sarah Bradshaw, Nick Hall, Céline Marleix-Bardeau , Nathalie Van Keymeulen, Ian Read and Karl Blake.
Wakeford repeatedly referred to his work as folk noir. Beginning with a mixture of a rough, bleak, primitive post punk sound and acoustic/folk elements, the band's music gradually evolved toward a lush, refined style, picking up classically trained players such as Eric Roger, Matt Howden, and Sally Doherty. In the mid-1990s, Sol Invictus spun off a side project called L'Orchestre Noir (later changed to Orchestra Noir) to explore an even more classically influenced direction. 2005 saw the departure of longtime contributors Roger and Blake, leading to a new line-up including Caroline Jago, Lesley Malone and Andrew King.
Fields were an Anglo-Icelandic electronic/indie band formed in London in 2006. After playing their first live shows they signed a deal with Atlantic Records, who allowed them to release through their own Black Lab Records set-up to record their 2007 debut album Everything Last Winter with producer Michael Beinhorn at Sun Studios, Dublin.
Vocalist Nick Peill instigated most of Fields' songs. With Peill, line-up was vocalist and keyboard player Þórunn Antonía, lead guitarist Jamie Putnam, drummer Henry Spenner, and bassist Matty Derham who later joined Does It Offend You, Yeah?.
Although recording work commenced on a follow-up album entitled 'Lost Frequencies' which would include the songs 'Sun In Your Eyes', 'Constantly', 'Are You Ready Yet?', 'Worst Love' and 'Call The Captain', the album remains unreleased.
The band split-up in 2009 after they lost their recording contract.