What does 1.8e-5 mean or stand for?

3 answers

e-5 is alternate notation for 10^-5
The e stands for the word exponent, sort of.
so what you have is
1.8 * 10^-5
which is 0.000018
The "e" is the power of 10 (exponent)

1.8E-5 = 1.8 * 10^-5 = 0.000018

It's a hold-over from the old FORTRAN floating-point days. E for single-precision (7 decimal places), D for double-precision (16 decimal places)
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