Improve accuracy of expf
Improve accuracy of expf

tc3t/qoot,tc3t/qoot,tc3t/qoot,tc3t/qoot,kirbyherm/root-r-tools,tc3t/qoot,kirbyherm/root-r-tools,kirbyherm/root-r-tools,kirbyherm/root-r-tools,tc3t/qoot,kirbyherm/root-r-tools,tc3t/qoot,kirbyherm/root-r-tools,tc3t/qoot,kirbyherm/root-r-tools,tc3t/qoot,tc3t/qoot