OPLOTERR Procedure

Standard Library procedure that overplots symmetrical error bars on any plot already output to the display device.

x = [1, 2, 3, 4]
y = [2, 1, 3, 2]
PLOT, x, y
error = [0.5, 0.25, 1, 0]
psym = 6
OPLOTERR, x, y, error, psym

Figure 2-59 In this example, OPLOTERR was used to plot error bars over the x and y vectors, using the square symbol at the data values.

Figure 2-60 In this example, OPLOTERR was used to plot error bars over the x and y vectors, using the square symbol at the data values.

x = INDGEN(7) + 1

; Generate the abscissas.

y = [2, 4, 5, 7, 6, 8, 12]

; Create a vector of ordinates.

bs = BSINTERP(x, y)

; Compute the B-spline interpolant.

bsval = SPVALUE(FINDGEN(100)/5, bs)

; Plot the interpolant.

PLOT, FINDGEN(100)/5, bsval, XRange = [0, 8], YRange = [0, 13]
err = MAKE_ARRAY(7, Value = 1)

; Create the error bar vector.

OPLOTERR, x, y, err, 6

; Overplot the data points, using square marker symbols and the
; error bars (see Figure 2-61).

Figure 2-61 Scattered data interpolant with overplotted data points and symmetric error bars.

Figure 2-62 Scattered data interpolant with overplotted data points and symmetric error bars.