Representing an exponent - what is acceptable to ACLiC

ROOT
1

Greetings all,

I have a script in which I have to fit to a function of form

G4 = (0.234*G2**(0.622)/(1-(1-0.234)*G2**(0.622)));

The above statement works fine as interpreted code, but when I try to compile it I get the following error

It is my understanding that this error means that my exponent call “**” is being interpreted by the compiler as a pointer.

I have been through the documentation and I can’t find what I am supposed to do to use an exponent and then compile code - I would like to avoid having to recast as “POW(a,b)” format if possible.

Is there an #include I should be using at the beginning of my file that is missing?

Any guidance or advice will be greatly appreciated.

Regards

2

Although ** is implemented in Cint as power, it isn’t standard C++. I believe you’re going to need to use pow() (sorry…).

Cheers,
Charles

3

Dear Charles,

Thanks for the response. I was aware that “**” was non-standard for C++ but I was hoping that there was a “magic” include file that would solve my problem for me.

If the only way that works would be to recast using pow(), then it would be simpler to always run these particular scripts in interpreted mode. Some of my equations would end up difficult to make sense of if recast using pow().

The affected class of scripts only occur at the final stages of analysis and long after the time consuming parts of the analysis are completed. I guess I’ll just have to live with the inelegance.