KPG1_AINDx

Obtains for an axis the equivalent index co-ordinates given axis values

Description:

This routine determines the indices within an axis array for a series of axis values. It assumes that the array is monotonically increasing or decreasing, and is approximately linear. This routine may be used for arbitrary 1-d arrays in addition to axes, provided these criteria are met.

A Newton’ s approximation method is used comparing the actual value with a linear approximation. The upper and lower bounds used to define the increment are adjusted given the deviation from the linear axis. Once the value lies between adjacent array elements the nearer (by linear interpolation) becomes the required index.

Invocation

CALL KPG1_AINDx( LBND, UBND, AXIS, EL, VALUE, INDEX, STATUS )

Arguments

LBND = INTEGER (Given)
The lower bound of the axis array.
UBND = INTEGER (Given)
The upper bound of the axis array.
AXIS( LBND:UBND ) = ? (Given)
The axis array.
EL = INTEGER (Given)
The number of values whose indices in the axis are to be found.
VALUE( EL ) = ? (Given)
The axis-array values.
INDEX( EL ) = ? (Returned)
The pixel indices of the values in the axis array. Notice that this is floating as fractional positions may be required.
STATUS = INTEGER (Given and Returned)
The global status.

Notes: