MATLAB: How to write this equation

equationqrite

Dear All, I have this equation in excel, what is the best way to write in matlab?
Y = 1.13+13/(1+EXP(7.57-15.5*LOG(x+0.0001)))
I tried this in matlab, but it did not give the same results for all values of x:
Y = 1.13+(13./(1+exp(7.57-15.5.*log(x+0.0001))));
x is a vector column of 200 values.

Best Answer

There is a difference between log and log10. What you have done in Excel is actually calculate the log10, because you omitted the base as an input. The log function in Matlab computes the natural logarithm. If you want to have the same effect, either put EXP(1) as the base in Excel, or use this in Matlab:
Y = 1.13+(13./(1+exp(7.57-15.5.*log10(x+0.0001))));