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Reciprocal Condition

Compute reciprocal condition of square matrix in 1-norm

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  • Reciprocal Condition block

Libraries:
DSP System Toolbox / Math Functions / Matrices and Linear Algebra / Matrix Operations

Description

The Reciprocal Condition block computes the reciprocal of the condition number for a square input matrix A.

Here is the equivalent MATLAB® code.

y = rcond(A)

or

y=1κ=1‖A−1‖1‖A‖1,

where κ is the condition number (κ ≥ 1), and y is the scalar output (0 ≤ y < 1).

The matrix 1-norm, ‖A‖1, is the maximum column-sum in the M-by-M matrix A.

‖A‖1=1≤j≤Mmax∑i=1M|aij|

For a 3-by-3 matrix:

Ports

Input

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Specify the input matrix as a square matrix.

Data Types: single | double

Output

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Reciprocal of the condition number for a square input matrix A, returned as a scalar.

If input is well conditioned, the output is near 1.0. If input is badly conditioned, the output is near 0.0.

Data Types: single | double

Block Characteristics

Data Types

double | single

Direct Feedthrough

no

Multidimensional Signals

no

Variable-Size Signals

no

Zero-Crossing Detection

no

References

[1] Golub, G. H., and C. F. Van Loan. Matrix Computations. 3rd ed. Baltimore, MD: Johns Hopkins University Press, 1996.

Extended Capabilities

Version History

Introduced before R2006a

See Also

Functions

Blocks