On Sat, 2005-03-05 at 00:00 -0700, Dave Benjamin wrote:
> On Fri, 2005-03-04 at 08:36 -0800, gf gf wrote:
> > Is there a better, more FP style, more Pythonic way to
> > write this:
> >
> > def compute_vectors(samples, dset):
> > vectors = {}
> > for d in dset:
> > vectors[d] = [sample.get_val(d) for sample in
> > samples]
> > return vectors
>
> You could use reduce:
>
> def compute_vectors(samples, dset):
> def add_entry(vectors, d):
> vectors[d] = [sample.get_val(d) for sample in samples]
> return vectors
> return reduce(add_entry, dset, {})
This could be further generalized:
def compute(xs, ys, f):
def add_entry(result, y):
result[y] = [f(x, y) for x in xs]
return result
return reduce(add_entry, ys, {})
Now, compute_vectors is just:
compute(samples, dset, lambda x, y: x.get_val(y))
You could even abstract the method call:
def method(name):
def _method(obj, *args, **kwds):
return getattr(obj, name)(*args, **kwds)
return _method
compute(samples, dset, method('get_val'))
Dave
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