Quick Filter Dictionary

[abcd]

Hi,
I have a dictionary which may contain various keys/values, however,
it will always contain 'name' and 'age' keys.

This dictionary is kept inside a class, such as....

class Person:
def __init__(self, name, age):
self.data = {'name' : name, 'age' : age}

def getData(self, includeNameAge= False):
if includeNameAge: return self.data
tmp = <shallow or deep copy of 'data'>
del tmp['name']
del tmp['age']
return tmp

The getdata method should return the data stored for the
person, however, it should be able to return the data excluding the
'name' and 'age'. Any suggestions on how to best implement this?
Keep in mind this sample code is meant to be an example, I realize
that a person would probably always want the name and age returned.

thanks

[abcd]

Re: Quick Filter Dictionary

On Mar 14, 7:29 am, "abcd" <codecr...@gmai l.comwrote:

Hi,
I have a dictionary which may contain various keys/values, however,
it will always contain 'name' and 'age' keys.
>
This dictionary is kept inside a class, such as....
>
class Person:
def __init__(self, name, age):
self.data = {'name' : name, 'age' : age}
>
def getData(self, includeNameAge= False):
if includeNameAge: return self.data
tmp = <shallow or deep copy of 'data'>
del tmp['name']
del tmp['age']
return tmp
>
The getdata method should return the data stored for the
person, however, it should be able to return the data excluding the
'name' and 'age'. Any suggestions on how to best implement this?
Keep in mind this sample code is meant to be an example, I realize
that a person would probably always want the name and age returned.
>
thanks

I guess one solution might be....

def getData(self, includeNameAge= False):
if includeNameAge: return self.data
return dict(filter(lam bda item: item[0] not in ('name', 'age'),
self.data.items ()))

any other suggestions, improvements?

[Bruno Desthuilliers]

Re: Quick Filter Dictionary

abcd a écrit :

On Mar 14, 7:29 am, "abcd" <codecr...@gmai l.comwrote:

>Hi,
> I have a dictionary which may contain various keys/values, however,
>it will always contain 'name' and 'age' keys.
>>
> This dictionary is kept inside a class, such as....
>>
> class Person:

Do yourself a favor : use new-style classes:
class Person(object):

> def __init__(self, name, age):
> self.data = {'name' : name, 'age' : age}

You may improve this part with kwargs:

def __init__(self, name, age, **kw):
kw.update(name= name, age=age)
self.data = kw

Also, and FWIW, object attributes are stored in self.___dict__. Do you
have a compelling reason to use yet another 'data' dict ?

> def getData(self, includeNameAge= False):
> if includeNameAge: return self.data
> tmp = <shallow or deep copy of 'data'>

tmp = self.data.copy( )

> del tmp['name']
> del tmp['age']
> return tmp

The problem with this implementation (as well as for the other below) is
that in the first case you return a reference to the data dict itself,
while in the second case you return a new dict.

p = Person('bibi', 42, foo='bar')
data = p.getData(True)
data['baaz'] = 'quux'
del data['name']
print p.data

p = Person('bibi', 42, foo='bar')
p.getData()
data['baaz'] = 'quux'
del data['foo']
print p.data

Better to *always* return a copy IMHO.

[Steve Holden]

Re: Quick Filter Dictionary

abcd wrote:

On Mar 14, 7:29 am, "abcd" <codecr...@gmai l.comwrote:

>Hi,
> I have a dictionary which may contain various keys/values, however,
>it will always contain 'name' and 'age' keys.
>>
> This dictionary is kept inside a class, such as....
>>
> class Person:
> def __init__(self, name, age):
> self.data = {'name' : name, 'age' : age}
>>
> def getData(self, includeNameAge= False):
> if includeNameAge: return self.data
> tmp = <shallow or deep copy of 'data'>
> del tmp['name']
> del tmp['age']
> return tmp
>>
> The getdata method should return the data stored for the
>person, however, it should be able to return the data excluding the
>'name' and 'age'. Any suggestions on how to best implement this?
>Keep in mind this sample code is meant to be an example, I realize
>that a person would probably always want the name and age returned.
>>
>thanks

>
>
I guess one solution might be....
>
def getData(self, includeNameAge= False):
if includeNameAge: return self.data
return dict(filter(lam bda item: item[0] not in ('name', 'age'),
self.data.items ()))
>
any other suggestions, improvements?
>

You might find

return dict((x,y) for (x, y) in self.data.iteri tems()
if x not in ('name', 'age'))

easier to understand. Or you might not ...

regards
Steve
--
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