Under the Radar (magazine)Under the Radar is an American music magazine that features interviews with accompanying photo-shoots. Each issue includes opinion and commentary of the indie music scene as well as reviews of books, DVDs, and albums. The magazine posts web-exclusive interviews and reviews on its website. Items are reviewed based on a rating system in which each album, book, and DVD receives a rating from 1 to 10. The magazine has been in publication since late 2001 and is issued three times per year.
Row echelon formIn linear algebra, a matrix is in echelon form if it has the shape resulting from a Gaussian elimination. A matrix being in row echelon form means that Gaussian elimination has operated on the rows, and column echelon form means that Gaussian elimination has operated on the columns. In other words, a matrix is in column echelon form if its transpose is in row echelon form. Therefore, only row echelon forms are considered in the remainder of this article. The similar properties of column echelon form are easily deduced by transposing all the matrices.
Gaussian eliminationIn mathematics, Gaussian elimination, also known as row reduction, is an algorithm for solving systems of linear equations. It consists of a sequence of operations performed on the corresponding matrix of coefficients. This method can also be used to compute the rank of a matrix, the determinant of a square matrix, and the inverse of an invertible matrix. The method is named after Carl Friedrich Gauss (1777–1855).
Elementary matrixIn mathematics, an elementary matrix is a matrix which differs from the identity matrix by one single elementary row operation. The elementary matrices generate the general linear group GLn(F) when F is a field. Left multiplication (pre-multiplication) by an elementary matrix represents elementary row operations, while right multiplication (post-multiplication) represents elementary column operations. Elementary row operations are used in Gaussian elimination to reduce a matrix to row echelon form.
No. 56 Squadron RAFNumber 56 Squadron, nicknamed the Firebirds for their ability to always reappear intact regardless of the odds, is one of the oldest and most successful squadrons of the Royal Air Force, with battle honours from many of the significant air campaigns of both the First and Second World Wars. During the First World War, the squadron had many aces amongst its ranks such as James McCudden, Albert Ball, Reginald Hoidge and Arthur Rhys-Davids, developing a fierce reputation for the unit.