Dictionary Comprehension - ValueError: too many values to unpack (expected 2)

Dictionary Comprehension - ValueError: too many values to unpack (expected 2) - Printable Version

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Dictionary Comprehension - ValueError: too many values to unpack (expected 2) - samRddhi - Dec-22-2017

Hi,

Trying to understand dictionary comprehension.

dGro = {"Cabbage": 2, "Carrot":3, "Peas":5, "LadyFinger":1}
print (dGro)
dGroD = {veg:kilo*2 for (veg,kilo) in dGro.items()}

print(dGroD)

The above code works, but when i try to double the kilo of vegetables by 2 with the below code

dGroD = {veg:kilo*2 for (veg,kilo) in dGro if(dGro[kilo] > 1)}

I get the below error

Error:
ValueError: too many values to unpack (expected 2)

What is wrong with the above code ?

Thanks

RE: Dictionary Comprehension - ValueError: too many values to unpack (expected 2) - squenson - Dec-22-2017

kilo is a value, so dGroD[kilo] doesn't make much sense. Try:

dGroD = {veg:kilo*2 for (veg,kilo) in dGro if kilo > 1}

This works as well:

dGroD = {veg: kilo * 2 for (veg, kilo) in dGro.items() if dGro[veg] > 1 }

RE: Dictionary Comprehension - ValueError: too many values to unpack (expected 2) - samRddhi - Dec-22-2017

(Dec-22-2017, 08:59 AM)squenson Wrote: kilo is a value, so dGroD[kilo] doesn't make much sense. Try:
dGroD = {veg:kilo*2 for (veg,kilo) in dGro if kilo > 1}
This works as well:
dGroD = {veg: kilo * 2 for (veg, kilo) in dGro.items() if dGro[veg] > 1 }

Thanks for the help Smile

, it works