Python scientific notation using D instead of E

Escualo picture Escualo · Dec 24, 2009 · Viewed 8.4k times · Source

Some results file produced by Fortran programs report double precision numbers (in scientific notation) using the letter D instead of E, for instance:

1.2345D+02
# instead of
1.2345E+02

I need to process huge amounts of this data using Python, and I just realized it cannot read the numbers in the D notation, for instance:

>>> A = 1.0D+01
  File "<stdin>", line 1
    A = 1.0D+01
           ^
SyntaxError: invalid syntax

Can I change my locale and let Python know that D means E? I really would not want to make a global search-and-replace!

Answer

Paul picture Paul · Dec 24, 2009

If you are dealing with lots of data and/or are doing a lot computations with that data, you might consider using the fortran-friendly numpy module which supports double-precision fortran format out of the box.

>>> numpy.float('1.5698D+03')
1569.8