## GR4_CURVE - GR8_CURVE

GR4_CURVE(NXY,X,Y,Z,VAR,PER,BVAL,EVAL,ERROR)

Plots a smooth curve from the (X,Y) values using the requested interpolant. Z is either a dummy argument or a parameter for the curve representation depending on the VAR value. VAR indicates which is the variable to use for interpolation. PER indicates whether the curve is periodic or not. BVAL and EVAL define the blanking value and the blanking tolerance (set EVAL negative to disable blanking checking). ERROR is an error flag set if the curve could not be produced. The current accuracy is used for the interpolation.

    Arguments :
            NXY     INTEGER         Input
            X       REAL (NXY)      Input
            Y       REAL (NXY)      Input
            VAR     CHARACTER*(*)   Input
            PER     LOGICAL         Input
            BVAL    REAL            Input
            EVAL    REAL            Input
            ERROR   LOGICAL         Output