errorbarlog.m

Symmetrical error bars for logarithmic Y-axis

ERRORBARLOG(X,Y,E,...) plots the graph of vector X vs. vector Y with a logarithmic Y-axis, using symmetrical bars about the data points, ie: the bars are such that Y is the geometric mean (instead of arithmetic mean) of the lower and upper bars. The total length of the error bar is 2E.

ERRORBARLOG has the same syntax as the original Matlab's ERRORBAR function. The only difference is that while ERRORBAR displays the bars symmetrically for a linear Y-axis (ie: Y is the arithmetic mean of the lower and upper bars), ERRORBARLOG displays them symmetrically for a logarithmic Y-axis.

Example:

x=logspace(1,3,20);
y=5*(1 + 0.5*(rand(1,20)-0.5)).*x.^(-2);
errorbarlog(x,y,y/2,'o-');