Error in 'eval' command: Typechecking failed. '-' only takes numbers

[raytroy]

I have tried many ways to get the difference between two numbers.

Here is what I have tried.

try 1: event=subscription data.price>0 AND data.endDate>0 | eval rr = (data.endDate - data.startDate) Results in Error in 'eval' command: Typechecking failed. '-' only takes numbers

try 2: event=subscription data.price>0 AND data.endDate>0 | convert num(data.startDate) num(data.endDate) | eval j = (data.endDate - data.startDate) Results in Error in 'eval' command: Typechecking failed. '-' only takes numbers

try 3: event=subscription data.price>0 AND data.endDate>0 | convert num(data.startDate) num(data.endDate) | table data.endDate data.startDate Has two columns of data and looks great.

data.endDate data.startDate

1397636176441 1397483257122

1397161336056 1397161260357

I would like to subtract data.endDate from data.startDate. 139763617641 - 1397483257122 =

I always get the error, Error in 'eval' command: Typechecking failed. '-' only takes numbers, for try 1 and try2. I thought it had to do with the data being a string and that is why I tried to convert (the second try). I tabled (try 3) and get output.

Thank you for your help.

[alai]

Use single quotes:

eval result = 'data.endDate' - 'data.startDate'

[HiroshiSatoh]

Use the period to become errors.Changed field names?

･････|eval data_endDate = data.endDate|eval data_startDate = data.startDate|eval rr=data_endDate- data_startDate

[raytroy]

I think I have solved the problem. The data.endDate was one level deep in the tree and the . was the only way to access the information inside those columns. Once I moved the data to the outer most tree level it worked. Lesson learned, make all the data on one level and don't embed object or events inside another event/dataset. Thank you for your help.