Column Space - Relation To The Left Null Space

Relation To The Left Null Space

The left null space of A is the set of all vectors x such that xTA = 0T. It is the same as the null space of the transpose of A. The left null space is the orthogonal complement to the column space of A.

This can be seen by writing the product of the matrix and the vector x in terms of the dot product of vectors:

where c1, ..., cn are the column vectors of A. Thus x = 0 if and only if x is orthogonal (perpendicular) to each of the column vectors of A.

It follows that the null space of is the orthogonal complement to the column space of A.

For a matrix A, the column space, row space, null space, and left null space are sometimes referred to as the four fundamental subspaces.

Read more about this topic:  Column Space

Famous quotes containing the words relation to, relation, left, null and/or space:

    Much poetry seems to be aware of its situation in time and of its relation to the metronome, the clock, and the calendar. ... The season or month is there to be felt; the day is there to be seized. Poems beginning “When” are much more numerous than those beginning “Where” of “If.” As the meter is running, the recurrent message tapped out by the passing of measured time is mortality.
    William Harmon (b. 1938)

    There is a relation between the hours of our life and the centuries of time. As the air I breathe is drawn from the great repositories of nature, as the light on my book is yielded by a star a hundred millions of miles distant, as the poise of my body depends on the equilibrium of centrifugal and centripetal forces, so the hours should be instructed by the ages and the ages explained by the hours.
    Ralph Waldo Emerson (1803–1882)

    It was a time of madness, the sort of mad-hysteria that always presages war. There seems to be nothing left but war—when any population in any sort of a nation gets violently angry, civilization falls down and religion forsakes its hold on the consciences of human kind in such times of public madness.
    Rebecca Latimer Felton (1835–1930)

    A strong person makes the law and custom null before his own will.
    Ralph Waldo Emerson (1803–1882)

    What a phenomenon it has been—science fiction, space fiction—exploding out of nowhere, unexpectedly of course, as always happens when the human mind is being forced to expand; this time starwards, galaxy-wise, and who knows where next.
    Doris Lessing (b. 1919)