# Qlik Sense App Development

Contributor II

## differnce in temperatures - ignore nulls

Hiya

I need to work out time difference between one date time stamp and another.

temperature of a room is taken on regular intervals during the day. This date time is recorded in the column, DateTimeTaken

=interval(max({<Temperature={'>=35'}>} DateTimeTaken) - min({<Temperature={'<=35'}>}DateTimeTaken) ,'h:mm' )

I need to calculate the time take for the room to reach 35.

sometimes the Temperature column is not filled in ''null'

1 Solution

Accepted Solutions
MVP

## Re: differnce in temperatures - ignore nulls

I guess it should be

=interval(Min({<Temperature={'>=35'}>} DateTimeTaken) - Max({<Temperature={'<=35'}>}DateTimeTaken) ,'h:mm' )

4 Replies
MVP

## Re: differnce in temperatures - ignore nulls

I guess it should be

=interval(Min({<Temperature={'>=35'}>} DateTimeTaken) - Max({<Temperature={'<=35'}>}DateTimeTaken) ,'h:mm' )

Not applicable

## Re: differnce in temperatures - ignore nulls

U can just use the max DateTimeTaken before it reached 35

=interval(max({<Temperature={'<=35'}>}DateTimeTaken),'h:mm' )

MVP

## Re: differnce in temperatures - ignore nulls

Could you maybe post some sample lines of data and your requested result?

Contributor II

## Re: differnce in temperatures - ignore nulls

Hi

worked brill thank you x