It looks unchanging. You don't need those extra columns start, end, cal_start etc.

Thank you for your answer. I've tried it in different ways. I've experimented like you said. I've erased some parts. Nevertheless, the result does not change. The AWC value needs to change the result. But the result does not change.

Hi Devran

As you know the available equations for calculating PDSI are really high in number and you need to consider several assumptions.

You know that we have many indices to computing drought event's condition, but in my opinion, PDSI is the most hardest one, since it has different conditional assumptions and needs many inputs.

In this regard, I found that there are several R packages for calculating it but understanding them to set some changes are not really easy.

However, I want to introduce a tool (DMAP) which is really proper and the user can modify the input data and change the amount of primary assumptions by typing them in the main screen.

See the link and pleasure to use it:

https://agrimetsoft.com/drought%20monitoring%20and%20prediction.aspx

Also, for better recognition of the equations of PDSI take a deep look to the attached paper of the Palmer paper.

Regards,

Nasrin

Hello Devran Çelik , did you find a solution for your problem?