Core Designer Certificate: HOL Question 5
I'm stuck on question 5! My formal is correct but there is no data showing up in the column. I successfully created a card for Univariate analysis of the 3 categories but don't know what I'm missing. Any guidance would be greatly appreciated. I'm applying for a sales position and would love to be certified prior to the interview process starting.
Some columns ( Oil production (Etemad & Luciana) (terawatthours), meat_prod_tonnes, and Food Balance Sheets: Eggs  Production (FAO (2017)) (tonnes) ) report country total data. Transform these three columns into percapita data.
 Hint 1: To convert from country “total” data to “percapita” data divide by the country's population.
 Hint 2: The Formula page in the reference documentation shows the proper syntax for using formulas to read column values when the column names include spaces.
 Hint 3: You will not need the original columns (including Population) for further analysis.
Thanks!
AA
Answers

Here's the formula I used numval("Oil production (Etemad & Luciana) (terawatthours)") / numval(Population)  DSS says the formula is valid but I'm this ExpressionError: Cannot parse to number: null in the sample output column. What am I missing? I tired to apply the formula to the whole dataset then on the individual columns and got nothing

denisemalan Dataiker, Dataiku DSS Core Designer, Dataiku DSS ML Practitioner, Dataiku DSS Adv Designer, Registered Posts: 19 Dataiker
Hi @admin4
,I would suggest looking at the names of your columns and which ones need to be converted using numval.
Hope that helps!
Best,
Denise, Dataiku Academy

Thanks for the tip. I'll apply and see what happens

curious if rounding to integers is the first right step or does that skew the data? @denisemalan

Hello, I am also having the same problem. I tried isolating the variables that needed to be converted using numval but that still didn't work. This is what I have so far:
numval("Oil production (Etemad & Luciana) (terawatthours)")/(Population)

denisemalan Dataiker, Dataiku DSS Core Designer, Dataiku DSS ML Practitioner, Dataiku DSS Adv Designer, Registered Posts: 19 Dataiker
Hi, @LeBronJames,
This formula works for me. Keep in mind the Oil production column has some nulls so you won't see output for every row.
Best,
Denise