I have a program which deals with nested data structures where the underlying type usually ends up being a decimal. e.g.
x={'a':[1.05600000001,2.34581736481,[1.1111111112,9.999990111111]],...}
Is there a simple pythonic way to print such a variable but rounding all floats to (say) 3dp and not assuming a particular configuration of lists and dictionaries? e.g.
{'a':[1.056,2.346,[1.111,10.000],...}
I'm thinking something like
pformat(x,round=3) or maybe
pformat(x,conversions={'float':lambda x: "%.3g" % x})
except I don't think they have this kind of functionality. Permanently rounding the underlying data is of course not an option.
This will recursively descend dicts, tuples, lists, etc. formatting numbers and leaving other stuff alone.
import collections
import numbers
def pformat(thing, formatfunc):
if isinstance(thing, dict):
return type(thing)((key, pformat(value, formatfunc)) for key, value in thing.iteritems())
if isinstance(thing, collections.Container):
return type(thing)(pformat(value, formatfunc) for value in thing)
if isinstance(thing, numbers.Number):
return formatfunc(thing)
return thing
def formatfloat(thing):
return "%.3g" % float(thing)
x={'a':[1.05600000001,2.34581736481,[8.1111111112,9.999990111111]],
'b':[3.05600000001,4.34581736481,[5.1111111112,6.999990111111]]}
print pformat(x, formatfloat)
If you want to try and convert everything to a float, you can do
try:
return formatfunc(thing)
except:
return thing
instead of the last three lines of the function.
A simple approach assuming you have lists of floats:
>>> round = lambda l: [float('%.3g' % e) if type(e) != list else round(e) for e in l]
>>> print {k:round(v) for k,v in x.iteritems()}
{'a': [1.06, 2.35, [1.11, 10.0]]}
>>> b = []
>>> x={'a':[1.05600000001,2.34581736481,[1.1111111112,9.999990111111]]}
>>> for i in x.get('a'):
if type(i) == type([]):
for y in i:
print("%0.3f"%(float(y)))
else:
print("%0.3f"%(float(i)))
1.056
2.346
1.111
10.000
The problem Here is we don't have flatten method in python, since I know it is only 2 level list nesting I have used for loop.
