Filtering a Dictionary with mutiple keys and multiple values per key

Question

I have a question regarding how to filter a dictionary using a loop.

Here is an example of the dictionary:

d = {'beta': ['ABC', '1', '5', '10', '15'],
     'lambda': ['DEF', '3', '30', '22.2', '150'],
     'omega': ['RST','15', '54.4', '150', '75']
}

How do I filter the dictionary to remove keys if the 3rd value in each key is < 100? In other words, after the if function, only omega should be left in the dictionary.
I tried:

for k, v in d.iteritems(): 
    r = float((d[key][2]))
    if r < float(100):
        del d[k]

But it did not work. Any thoughts? New to python programming here.

The new dictionary should just leave the omega key since 150 is greater than 100.

Answer 1

def cast_values(v):
    try:
        return float(v)
    except ValueError:
        return v

new_d = {k:[ cast_values(i) for i in v ] for k,v in d.items() if float(v[3]) > 100}

Results:

new_d = {'omega': ['RST', 15, 54.4, 150, 75]}