Python: zip two lists together without truncation

Question

I have two lists: ``` frame = ["mercury", "noir", "silver", "white" ] seat_colors = [ "coconut white", "yello", "black", "green", "cappuccino", "orange", "chrome", "noir", "purple", "pink", "red", "matte", "gray", "bermuda blue" ] ``` I'm trying to combine them to a single list where every frame is uniquely matched with every seat color. I'd like to use `zip()` like so: ``` In [3]: zip(frame, colors) Out[3]: [('mercury', 'coconut white'), ('noir', 'yello'), ('silver', 'black'), ('white', 'green')] ``` But it truncates to the length of the smallest list. I know I can iterate through the lists with: ``` In [5]: for f in frame: for c in colors: print "%s, %s" %(f, c) Out [5]: mercury, coconut white mercury, yello mercury, black mercury, green mercury, cappuccino mercury, orange mercury, chrome mercury, noir mercury, purple mercury, pink mercury, red mercury, matte mercury, gray mercury, bermuda blue noir, coconut white noir, yello noir, black noir, green .... ``` But I'd like the to be s…

Accepted Answer

Use `itertools.izip_longest()` to keep zipping until the longest sequence has been exhausted.

This uses a default value (defaulting to `None`) to stand in for the missing values of the shorter list.

However, your output is creating the product of two lists; use `itertools.product()` for that:

```
from itertools import product

for a_frame, color in product(frame, seat_colors):
    print '{}, {}'.format(a_frame, color)
```

The two concepts are quite different. The `izip_longest()` approach will produce `len(seat_colors)` items, while the product produces `len(seat_colors) * len(frame)` items instead.

Python: zip two lists together without truncation

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