Chromatography Forum

We would like to generate a custom field to monotor how many injections we have in each project. Say it is like an injection ID or sample ID. We are thinking use a letter and 5 digits to ID injections. The letter represent LC systems. numbers rerepresent sample/injection.

Could any one tell me how to do it?

Thank you very much.


PS. How to do custom field for calculations?

I'm not certain how one would write such a field, but scrolling down to the bottom of the "Injections" tab and checking the number of the last populated line should give you a pretty good idea...

you can make a custom intersample custom field

%.%.%.SUM(This is where it gets tricky)

You want to add up how many injections you have but you may have multiple results per injection. So you only want to add the injection one time. If you multiply each injection id by zero if the result number is greater than 1 you can replace theresult with zero in the summation thus adding only the injections for the first result.

I know that is confusing. Take a look at this math:

if injection ID is greater than zero and result ID = 1, multiply by 1
else mulitply by zero.
Add up all the results in the project and you have your number of injections.

%.%.%.SUM(GT(Injection ID,0)*EQ(Result Number,1))

Ensure that the custom field is not set to result set only.

Also, this will slow down your processing times, so only include Summarize Custom Fields in the sample sets that you want this value.
Good luck

Hi,
Just a quick word of caution, a custom field is not the most robust way of counting injections per project.

If a more robust method of counting injections is required, this value should be calculated using Empower’s toolkit.

Alternatively, if you have your own Oracle license, you could have your Oracle DBA create a count against the database.