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pythonlocalescientific-notation

Python scientific notation using D instead of E


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!


Solution

  • The simplest way, from your Python program, would be just to add a step before you interpret each entry:

    >>> val = "1.5698D+03"  # 1,569.8
    >>> print float(val.replace('D', 'E'))
    1569.8