Source: utils/plot/hs_errplot.pro
HS_ERRPLOT Overplot error bars over a previously drawn plot. CATEGORY: J6 - plotting, graphics, one dimensional. CALLING SEQUENCE: HS_ERRPLOT, Low, High ;X axis = point number HS_ERRPLOT, X, Low, High ;to specify abscissae INPUTS: Low = vector of lower estimates, = to data - error. High = upper estimate, = to data + error. OPTIONAL INPUT PARAMETERS: X = vector containing abscissae. KEYWORD Parameters: HORIZONTAL if set and non-zero, then plot the error bars || to the x-axis OUTPUTS: None. COMMON BLOCKS: None. SIDE EFFECTS: Overplot is produced. RESTRICTIONS: Logarithmic restriction removed. PROCEDURE: Error bars are drawn for each element. For example: Y = data values, ERR = symmetrical error estimates: PLOT,Y ;Plot data HS_ERRPLOT, Y-ERR, Y+ERR ;Overplot error bars. If error estimates are non-symetrical: PLOT,Y HS_ERRPLOT, Upper, Lower ;Where upper & lower are bounds. To plot versus a vector of abscissae: PLOT,X,Y ;Plot data. HS_ERRPLOT,X,Y-ERR,Y+ERR ;Overplot error estimates. MODIFICATION HISTORY: DMS, RSI, June, 1983. Joe Zawodney, LASP, Univ of Colo., March, 1986. Removed logarithmic restriction. DMS, March, 1989. Modified for Unix IDL. SJT (U. of Bham). Remove width, add HORIZONTAL. (Mar 1992) Make loop limits long: 3/5/02; SJT