What dose d-8 mean in Fortran?

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The term "d-8" in Fortran signifies a double precision representation of a floating-point number. Specifically, "2.0d-8" is equivalent to "2.0e-8," but it is stored as a double precision real number, which offers greater accuracy than single precision. In FORTRAN 77, this would be declared using REAL*16 instead of REAL*8. This distinction is crucial for developers working with numerical computations requiring high precision.

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What dose "d-8" mean in Fortran?

Dear friends;
What dose "d-8" mean in Fortran?
Thanks
 
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2.0d-8 is the same value as 2.0e-8 except that it's stored as a double precision real number instead of single precision. In FORTRAN 77 it would be declared as REAL*16 instead of REAL*8.
 


Much thanks to jtbell ;

you mean 2.0d-8 is equal to 2*10^ (-8) ?
 


Yes.
 

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