topic Calculate average, count and standard deviation with tMap in Talend Studio

Calculate average, count and standard deviation with tMap

Anonymous — Tue, 11 Dec 2018 18:00:26 GMT

Hello,

Is there any way to calculate the average, standard deviation and count data of some columns?

I know that it is possible to do it with tggregateRow, but I need to use the results of these values (average, standard deviation and count ) in a tMap to perform other calculations with them, so I would like to simplify everything in a single component (tMap).

This in my input information (the columns comes from an operation in a tAggregateRow component):

I need to calculate (as variables in tMap) the average and standard deviation of columns 'Frecuencia' and 'Repeticion' and count how many different data there's in column 'name'.

Then I need to do some others operations (like multiplications, divisions, square root, addition, subtraction and others) between this results and those two columns.

It is possible? Somebody please say yes.

Thanks!!

Re: Calculate average, count and standard deviation with tMap

Anonymous — Wed, 12 Dec 2018 03:57:24 GMT

Hi,

My suggestion would be to do the aggregation operations using taggregaterow component itself and store the output data to a thashoutput.

Then use the data from hash by reading it again using thashinput and join with main data in tmap for downstream calculations. It will be easy and less time consuming method.

I would suggest you to try based on this method and if you are stuck somewhere, please feel free to comeback with job and component screenshots. We are always here to help you 🙂

Warm Regards,

Nikhil Thampi

Re: Calculate average, count and standard deviation with tMap

Anonymous — Wed, 12 Dec 2018 20:43:28 GMT

Thank you VERY much Nikhil, you have been SO helpful.