[portland] Reformatting Data Files

Ethan Furman ethan at stoneleaf.us
Tue Mar 22 21:37:49 CET 2011

Rich Shepard wrote:
>   This has worked flawlessly for some of the exported spreadsheet pages.
> Now, however, I have some pages that include the units for the measured
> parameters (e.g., mg/L) which is the third-to-last column in the postgres
> table.
>       outdata.writerow([location, sampdate[i], row[0], float(row[i])])

How about a function that either floats your string, or returns the 
string if it's not a number?

Something like this:

--> def flt_or_str(unk):
...     try:
...         return float(unk)
...     except ValueError:
...         return unk
--> float("1")
--> float("hello")
Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
ValueError: invalid literal for float(): hello
--> flt_or_str("1")
--> flt_or_str("829mg/L")

Then your line of codes becomes:

   outdata.writerow([location, sampdate[i], row[0], flt_or_str(row[i])])

Hope this helps!


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