%N pgerry %F $MIR/src/pgerry.f
%D Vertical error bar
%B
      SUBROUTINE PGERRY (N, X, Y1, Y2, T)
      INTEGER N
      REAL X(*), Y1(*), Y2(*)
      REAL T

 Plot vertical error bars.
 This routine draws an error bar only; to mark the data point in
 the middle of the error bar, an additional call to PGPT or
 PGERRX is required.

 Arguments:
  N      (input)  : number of error bars to plot.
  X      (input)  : world x-coordinates of the data.
  Y1     (input)  : world y-coordinates of top end of the
                    error bars.
  Y2     (input)  : world y-coordinates of bottom end of the
                    error bars.
  T      (input)  : length of terminals to be drawn at the ends
                    of the error bar, as a multiple of the default
                    length; if T = 0.0, no terminals will be drawn.

 Note: the dimension of arrays X, Y1, and Y2 must be greater
 than or equal to N. If N is 1, X, Y1, and Y2 may be scalar
 variables or expressions, eg:
       CALL PGERRY(1,X,Y+SIGMA,Y-SIGMA)
