Undefined function 'log10' for input arguments of type 'embedded.fi'.

Dear All,

Can you help me to understand this error message and how to avoid these errors?

Here is the longer version of the message:

Undefined function 'log10' for input arguments of type 'embedded.fi'.

Error in parameterFun (line 9)
part2 = log10(part1);

Error in procDataFit>@(x,f)parameterFun(x,f)

The error emerges when I try to use the optimization toolbox to do a curve fitting. The equation for this work is stored in a separate function file (the code is below) and I call the function as

x = [fr(i),g0,K,offset];
    fun = @(x,f)parameterFun(x,f);
    x = lsqcurvefit(fun,x,fi,RINData);

------------ the code of annonymous function parameterFun.m -----------

function minRin = parameterFun(x,f)
dFactor = ( x(2) + x(3));
part1 = ((f.*1e6).^2+(dFactor./(2.*pi)))
part2 = log10(part1);
minRin = x(4) + 10*part2;

Answer 1

[Ahmed raafat]

to get log10 for numeric data you could use this old rule

log(x) to base y = ln(x)/ln(y)

so log10(x)

you can change it to

log(x)/log(10)

Answer 2

[Walter Roberson]

log is not supported by fi at all, not even by the CORDIC algorithms.

You might be interested in https://www.quinapalus.com/efunc.html or in http://people.sc.fsu.edu/~jburkardt/f_src/fn/fn.html