##
diagonal entry

Overview page. Subjects: Mathematics.

For a square matrix [*a*
_{
ij
}], the diagonal entries are the entries *a*
_{11}, *a*
_{22},…, *a*
_{
nn
}null...

##
diagonal entry

in** The Concise Oxford Dictionary of Mathematics**

January 2009; p ublished online January 2009 .

Reference Entry. Subjects: Pure Mathematics. 26 words.

For a square matrix [*a*
_{
ij
}], the diagonal entries are the entries *a*
_{11}, *a*
_{22},…,

##
diagonal entry

in** The Concise Oxford Dictionary of Mathematics**

January 2014; p ublished online September 2014 .

Reference Entry. Subjects: Pure Mathematics. 28 words.

For a square matrix [*a*
_{
ij
}], the diagonal entries are the entries *a*
_{11}, *a*
_{22},…, *a...*

##
diagonal entry

Overview page. Subjects: Mathematics.

For a square matrix [*a*
_{
ij
}], the diagonal entries are the entries *a*
_{11}, *a*
_{22},…, *a*
_{
nn
}null...

##
scalar matrix

in** The Concise Oxford Dictionary of Mathematics**

January 2009; p ublished online January 2009 .

Reference Entry. Subjects: Pure Mathematics. 36 words.

A diagonal matrix where all the entries in the leading diagonal are equal, to *k* say, and all other entries

##
tridiagonal matrix

Overview page. Subjects: Computing.

A square matrix with zero entries everywhere except on the main diagonal and the neighbouring diagonal on either side.

##
tridiagonal matrix

in** The Concise Oxford Dictionary of Mathematics**

January 2009; p ublished online January 2009 .

Reference Entry. Subjects: Pure Mathematics. 21 words.

A square matrix with zero entries everywhere except on the main diagonal and the neighbouring diagonal on either side.

##
tridiagonal matrix

in** The Concise Oxford Dictionary of Mathematics**

January 2014; p ublished online September 2014 .

Reference Entry. Subjects: Pure Mathematics. 21 words.

A square matrix with zero entries everywhere except on the main diagonal and the neighbouring diagonal on either side.

##
trace

Overview page. Subjects: Mathematics.

The trace of a square matrix is the sum of the entries in the main diagonal.

##
diagonal matrix

in** The Concise Oxford Dictionary of Mathematics**

January 2009; p ublished online January 2009 .

Reference Entry. Subjects: Pure Mathematics. 17 words.

A square matrix in which all the entries not in the main diagonal are zero.

##
trace

in** The Concise Oxford Dictionary of Mathematics**

January 2009; p ublished online January 2009 .

Reference Entry. Subjects: Pure Mathematics. 17 words.

The trace of a square *matrix is the sum of the entries in the *main diagonal.

##
diagonal matrix

in** The Concise Oxford Dictionary of Mathematics**

January 2014; p ublished online September 2014 .

Reference Entry. Subjects: Pure Mathematics. 17 words.

A square matrix in which all the entries not in the main diagonal are zero.

##
trace

in** The Concise Oxford Dictionary of Mathematics**

January 2014; p ublished online September 2014 .

Reference Entry. Subjects: Pure Mathematics. 19 words.

The trace of a square *matrix is the sum of the entries in the *main diagonal.

##
scalar matrix

Overview page. Subjects: Mathematics.

A diagonal matrix where all the entries in the leading diagonal are equal, to *k* say, and all other entries are zero. Multiplication by this matrix is equivalent to multiplication by the...

##
triangular matrix

Overview page. Subjects: Computing.

A square matrix that is either lower triangular or upper triangular. It is lower triangular if all the entries above the main diagonal are zero, and upper triangular if all the entries...

##
scalar matrix

in** The Concise Oxford Dictionary of Mathematics**

January 2014; p ublished online September 2014 .

Reference Entry. Subjects: Pure Mathematics. 36 words.

A diagonal matrix where all the entries in the leading diagonal are equal, to *k* say, and all other entries are zero. Multiplication by this matrix is equivalent to multiplication by the...

##
triangular matrix

in** The Concise Oxford Dictionary of Mathematics**

January 2014; p ublished online September 2014 .

Reference Entry. Subjects: Pure Mathematics. 40 words.

A square matrix that is either lower triangular or upper triangular. It is lower triangular if all the entries above the main diagonal are zero, and upper triangular if all the entries...

##
main diagonal

Overview page. Subjects: Mathematics.

In the *n*×*n* matrix [*a*
_{
ij
}], the entries *a*
_{11}, *a*
_{22},…, *a*
_{
nn
} form the main diagonal.

##
diagonally dominant matrix

in** The Concise Oxford Dictionary of Mathematics**

January 2009; p ublished online January 2009 .

Reference Entry. Subjects: Pure Mathematics. 73 words.

A *symmetric matrix where the absolute value of the entries in the main diagonal is not less than the

##
main diagonal

in** The Concise Oxford Dictionary of Mathematics**

January 2014; p ublished online September 2014 .

Reference Entry. Subjects: Pure Mathematics. 25 words.

In the *n*×*n* matrix [*a*
_{
ij
}], the entries *a*
_{11}, *a*
_{22},…, *a*
_{
nn
} form the main diagonal....

##
Gerschgorin's Theorem

Overview page. Subjects: Mathematics.

All the characteristic values of a square complex matrix **A** lie within the circles centred on each entry in the leading diagonal *a*
_{
ii
}, with radius