Im adding a specialised formula to a calculator, and it uses the Ln/ln function which is often on scientific calculators, how do i get this function to work in c++?

The formula is as follows:

'formula: pl * (10*diff + 10*creat +2*lines)

------------------------------------------

150 * (Ln(pl/1.5))'

Can anyone help?

## Recommended Answers

Jump to Post`#include <cmath>`

Use the 'log' function (which computes the natural logarithm).

Jump to PostSurely you meant

`x/(150*log(pl/1.5));`

I removed the multiplication sign after 'log' (which made it treated like a variable instead of a function name).

Also, as you wrote it, log(pl/1.5) would have been on the top of the fraction, so I added parentheses to put it on …

Jump to PostTry x/(150*log((double)(pl/1.5))); since log takes a double as its argument.

Jump to Postthe probleme is that you have declared log as a float. and a float is not a function and a float variable cant be used as a function.

so ether change (150*log(pl/1.5)); to (150*std::log(pl/1.5));

or remove the log float.

Jump to PostBah namespaces. Use std::log instead of log.

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Rashakil Fol
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