INVERT Function

Returns an inverted copy of a square array.

Usage

    result = INVERT(array[, status])

Input Parameters

array—Two-dimensional square array. May be of any data type except string.

Output Parameters

status—(optional) The name of a scalar variable used to accumulate errors from singular or near-singular arrays. Possible values are:

  • 0—Successful completion.

  • 1—A singular array, indicating that the inversion is invalid.

  • 2—A warning that a small pivot element was used and it is likely that significant accuracy was lost.

Returned Value

result—An inverted copy of array.

Keywords

None.

Discussion

An input array of double-precision floating-point data type returns a result of identical type. An input array of any other type yields a result of single-precision floating-point data type.

Errors are accumulated in the optional status parameter, or the math error status indicator. This latter status may be checked using the CHECK_MATH function.

Note: Unless double-precision floating-point values are used for array, round off and truncation errors may occur, resulting in imprecise inversion.

INVERT uses the Gaussian elimination method (whose objective is the transformation of the given system into an equivalent system with upper-triangular coefficient matrix).

See Also

CHECK_MATH,  DETERM,  LUBKSB,  LUDCMP,   TRANSPOSE