fString Nested forLoop - Printable Version

fString Nested forLoop - Printable Version

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fString Nested forLoop - pcsailor - Oct-13-2018

Hi all,
I'm learning about f-strings and I know in theory nested for loops can be turned into a simpler f-string, but I'm not sure how.

rows = range(1, 10)
columns = range(1, 5)
for row in rows:
  for col in columns:
    wb.active.cell(row, col).value = 'fString_forLoop'

Any clues?
thanks,
phil

RE: fString Nested forLoop - buran - Oct-13-2018

wb.active.cell(row, col).value = f'row:{row}, column:{col}'

RE: fString Nested forLoop - pcsailor - Oct-13-2018

Hi,
Thanks for the code line.
Regarding that f-String:

wb.active.cell(row, col).value = f'row:{row}, column:{col}'

can we break this down a bit?

wb.active # openpyxl method to assign an active worksheet
.cell # openpyxl method to activate a spreadsheet cell
(row, col) # where are you pulling this from?  The only usable code from above is 'rows' & 'columns' (the variable names)
.value # openpyxl method to assign a value within a cell
 =  # assignment operator
f' # python declaration for the start of a f-String
row: # where is this from?
{row},  # what is this pointing to?
column: # where is this from?
{col} # what is this pointing to?
' # end of python f-string

thanks,
phil

RE: fString Nested forLoop - buran - Oct-13-2018

'row:{row}, column:{col}' is string literal. It uses some basic string formatting. I.e. what is enclosed in curly brackets will change. Check https://docs.python.org/3/library/string.html#format-string-syntax
from your enumeration - lines 7 and 9 are just example of text. It could be whatever you want.
lines 8 and 10 uses the f-string formatting to pass variables to string.

RE: fString Nested forLoop - pcsailor - Oct-13-2018

what about line 3?

RE: fString Nested forLoop - volcano63 - Oct-13-2018

(Oct-13-2018, 09:45 AM)pcsailor Wrote: what about line 3?

They come from those lines - in Python, you loop over iterables dicrectly, without indices

for row in rows:
  for col in columns:

RE: fString Nested forLoop - pcsailor - Oct-13-2018

ok, maybe I'm looking at this wrong.
I'm sorry if this is so basic. I feel pretty dumb right now >:

I thought with the f-string I would only have this code:

rows = range(1, 10)
columns = range(1, 5)
wb.active.cell(row, col).value = f'row:{row}, column:{col}'

and this code is not used:

for row in rows:
  for col in columns:
    wb.active.cell(row, col).value = 'fString_forLoop'

thanks,
Phil

RE: fString Nested forLoop - volcano63 - Oct-13-2018

(Oct-13-2018, 09:55 AM)pcsailor Wrote: ok, maybe I'm looking at this wrong.
I'm sorry if this is so basic. I feel pretty dumb right now >:

I thought with the f-string I would only have this code:
rows = range(1, 10)
columns = range(1, 5)
wb.active.cell(row, col).value = f'row:{row}, column:{col}'

You can process tables as a whole in pandas/numpy - though building initial values may still require either looping or comprehension (comprehension being a looping in not so deceiving disguise)