Name

condnb_logcond — Computes the condition number of the log function.

Calling Sequence

   [c,y] = condnb_logcond ( x )
   
   

Parameters

x :

a n-by-m matrix of doubles

c :

a n-by-m matrix of doubles, the condition number

y :

a n-by-m, matrix of doubles, the function values

Description

Computes the condition number of the exp function. This function is badly conditionned near x=1.

Examples

[c,y] = condnb_logcond ( 2 )
[c,y] = condnb_logcond ( 1 )

// Plot the condition number of log, for positive values.
h = scf();
x = linspace(1.e-10,10,1000);
c = condnb_logcond ( x );
plot(x,c)
// Turn on log-scale
h.children.log_flags = "nln"

   

Authors

Michael Baudin, DIGITEO, 2010