What are these two things in below commands?

Hello Experts,
In this i want to know that what are those two values in these commands of GPS?
one (right one) i think but what is the second one ?
Can anyone please help me with this ? it will be very helpful.

/gps/hist/point 1.0023 202.26
/gps/hist/point 1.0162 207.42
/gps/hist/point 1.0304 212.75
/gps/hist/point 1.0447 218.26
/gps/hist/point 1.0592 223.95
/gps/hist/point 1.0739 229.83
/gps/hist/point 1.0888 235.92
/gps/hist/point 1.104 232.96
/gps/hist/point 1.1193 224.59
/gps/hist/point 1.1349 216.5
/gps/hist/point 1.1506 208.66
/gps/hist/point 1.1666 201.06
/gps/hist/point 1.1828 193.7
/gps/hist/point 1.1993 186.58
/gps/hist/point 1.2159 179.69
/gps/hist/point 1.2328 173.02

Hi Priyanshu,

You can find information about all of the GPS commands at: Geant4 General Particle Source — Book For Application Developers 10.7 documentation

The documentation explains the /gps/hist/point command as:

As decribed above, the first number refers to the upper edge of the histogram bin you are defining (if you are defining a histogram and not a point-wise distribution) and the second number is the weighting factor associated with that histogram bin. A GPS defined histogram can be used to set the energy spectra, position, or angular distribution of a primary particle you are generating. You will have to see how the /gps/hist/type command is defined in your macro file to determine what the histogam you shared in your above post is being used for.

Possibly someone can respond to this forum post to clarify the behavior of the first histogram bin. I believe since a lower bin edge has not been defined, that the weighting associated with the first /gps/hist/point is discarded since that bin does not have a lower defined edge. But I am not certain about this, so I would be happy to have someone correct me if this is inaccurate.

I hope you find this helpful,


Thank you so much for your reply!
yes, in my file i am using /gps/hist/type Arb.
I am using this primary.mac file.
primary.txt (25.7 KB)
but, in this file they have used another model, and i want to used another GCR model for that i am having a file which contains energy points generated from that model.
**Then, my question is how i will know the bin number, associated with that energy points ?**if i am having only energy points ?
Can you please help me with this, it will be very helpful.
Thanks in advance!

Hi Priyanshu,

I’m not sure what you mean about a file which contains energy points generated from a model. Could you elaborate on what those energy points are? or provide the structure of that file.


Thanks for your reply!
This is the spectra that is invoked through GPS (/gps/hist/point 1.0023 202.26 and like wise).

so from this spectra i can see that in the primary.mac file (attached in the .txt format due the constrains of forum) below:-
primary.txt (25.7 KB)
so in this first column of /gps/hist/point 1.0023 202.26, i can see that first one is energy that is varying from 1MeV to 100000 MeV but what is in the second column, is it flux ? really i don’t understand this because it is starting from 200 and then decreasing then increasing and like wise.
So I just wanted to know that what it is actually.
This is the mac file of radioprotection example (advanced) .
Can you please tell me what is this ?

sorry to bother you for this. i got the answer. in this first one is energy and second one is differential flux.
Thank you for the help!