the customization point - accept const char* and convert to int - then call index method of base class

Number of axes (dimensions) of histogram

Reset bin counters to zero

this only works for axes with compatible bin type and will throw a runtime_error otherwise

the following is highly optimized code that runs in a hot loop; please measure the performance impact of changes

Construct axis with n bins over real range [lower, upper). * * \param n number of bins. * \param lower low edge of first bin. * \param upp

note: this only works for axes with compatible value type

Total number of bins in the histogram (including underflow/overflow)

Returns the number of bins without overflow/underflow.