[exec cmd for cmd in cmds]

[Schüle Daniel]

Hello all,

p = "z%i = complex(1-1e-%i, 1-1e-%i)"
lst = [p % (i,i,i) for i in range(10, 30)]
for item in lst: .... exec item
....
p = "z%i = complex(1-1e-%i, 1-1e-%i)"
lst = [p % (i,i,i) for i in range(10, 30)]
[exec item for item in lst] File "<stdin>", line 1
[exec item for item in lst]
^
SyntaxError: invalid syntax
is this prohibited for some reasons or is this just happens to be
disallowed?
this is one more cool way p = "z%i = complex(1-1e-%i, 1-1e-%i);"
c = reduce(lambda x,y: x+y, [p % (i,i,i) for i in range(20,30)])
exec c
and one more :) p = "z%i = complex(1-1e-%i, 1-1e-%i);"
c = "".join([ p % (i,i,i) for i in range(20,30) ])
exec c

Regards, Daniel

[Diez B. Roggisch]

Schüle Daniel wrote:

Hello all,

>>> p = "z%i = complex(1-1e-%i, 1-1e-%i)"
>>> lst = [p % (i,i,i) for i in range(10, 30)]
>>> for item in lst: ... exec item
... >>>
>>> p = "z%i = complex(1-1e-%i, 1-1e-%i)"
>>> lst = [p % (i,i,i) for i in range(10, 30)]
>>> [exec item for item in lst] File "<stdin>", line 1
[exec item for item in lst]
^
SyntaxError: invalid syntax >>>
is this prohibited for some reasons or is this just happens to be
disallowed?
exec is a statement. And statements aren' allowed in the _expression_ of a
list-comprehension.
this is one more cool way >>> p = "z%i = complex(1-1e-%i, 1-1e-%i);"
>>> c = reduce(lambda x,y: x+y, [p % (i,i,i) for i in range(20,30)])
>>> exec c
and one more :) >>> p = "z%i = complex(1-1e-%i, 1-1e-%i);"
>>> c = "".join([ p % (i,i,i) for i in range(20,30) ])
>>> exec c

If you think so :) Ususally people go for dictionaries in such cases.

Diez

[Schüle Daniel]

[...]

If you think so :) Ususally people go for dictionaries in such cases.

you are right, I didn't think about dictionaries

p = "complex(1-1e-%i, 1-1e-%i)"
d={}
[d.update({i:eval(p % (i,i))}) for i in range(20,30)]

[None, None, None, None, None, None, None, None, None, None]

so now the work is complete :)

Regards

[Scott David Daniels]

Schüle Daniel wrote:

you are right, I didn't think about dictionaries

>>> p = "complex(1-1e-%i, 1-1e-%i)"
>>> d={}
>>> [d.update({i:eval(p % (i,i))}) for i in range(20,30)]

[None, None, None, None, None, None, None, None, None, None]

so now the work is complete :)

Regards

Really, isn't this clearer?:

d = {}
for i in range(20, 30):
v = 1. - 10. ** -i
d[i] = complex(v, v)

If you must repair the mess above, try:

p = "complex(1-1e-%i, 1-1e-%i)"
d = dict([(i, eval(p % (i, i))) for i in range(20, 30)])

Strive to be clear first, terse second given the first is still
achieved.

--Scott David Daniels
sc***********@acm.org