[Tutor] Converting a sequence of dictionaries to a single dictionary

[Alan Gauld]

On 22/06/16 01:41, Ek Esawi wrote:

> I am trying to read a csv file via DictReader and produce a single
> dictionary without fieldnames; that is, I just want a single dictionary
> that contains tests as keys and grades as values as shown below in my
> sample file.

OK, As you've discovered that's not what the csv reeaders do.
They produce a data structure per line. Thats because CSV files
usually contain one discrete data record per line. If you want to pull
all the records into a single dictionary you will need to do that
yourself, probably using a standard tuple based reader.

> I want to create a single dictionary with only Tests and Grades; that’s
> {Test1:A,Test2:b,Test3:c etc.}. I tried several ways but nothing worked.

> File

> Test     Grade
> Test1   A
> Test2   B
> Test3   C

So the reader will give you
[('Test1','A'),('Test2','B'),...]

So you need to take the list of tuples and put
them in a dict. Luckily that's exactly what the dict()
function does when given a list of tuples.

>>> dict([(1,2),(3,4)])
{1: 2, 3: 4}
>>>

So you just need to call dict() on your reader data.


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Alan G
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