codoor
Newbie

I try use hspice2012 and hspice2021 to generate a variable, whose distribution is gauss.
I define this variable in netlist as follow:
.param globw=agauss(0, 1, 3)
.param globwidth=globw
and I can get the sample point in xxx.mc0 in hspice2021 and in xxx.ms0 in hspice2012, and then I use the numpy in python to get the std and mean of the sample.
i find the mean and std of sample point generated by hspice2021 is 0 and 1, but the mean and std of sample point generated by hspice2012 is 0 and 1/3.
I see the hspice user guild said agauss(0, 1, 3) means a gauss distribution which mean is 0 and std is 1/3.
So, what happens in hspice2021???
and the head of sample data generated by hspice2021 as follow:
$DATA1 SOURCE='PrimeSim HSPICE' VERSION='S-2021.09
$OPTION MEASFORM=1
$ This file format is subject to change
$ The seperator is
:
$index=1 is a nominal sample in Monte Carlo.
$option ignore_global_variation = no
$option ignore_local_variation = no
$option ignore_aging_variation = yes
$option ignore_interconnect_variation = no
$option ignore_spatial_variation = no
$option ignore_variation = no
$option sampling_method = srs
$option normal_limit = 20.0000
$option replicates = 1
$option random_generator = MCG
$option seed = 1
$option stream = 1
$option output_sigma_value = 1
$option use_agauss_format = yes
$option screening_method = pearson
$Global Variable number: 1
$Local Variable number: 0
$Aging Variable number: 0
$.TITLE 'four resistors
$.Option Sampling_Method = External Block_Name = extern_data
$.data extern_data
$ Column headers
$ Col Name and distribution data
$ 1 index
$ 2 globwidth
:globw
:IGNC 1 agauss 0.000000 1.000000 1.000000
index globwidth
:globw
:IGNC
I define this variable in netlist as follow:
.param globw=agauss(0, 1, 3)
.param globwidth=globw
and I can get the sample point in xxx.mc0 in hspice2021 and in xxx.ms0 in hspice2012, and then I use the numpy in python to get the std and mean of the sample.
i find the mean and std of sample point generated by hspice2021 is 0 and 1, but the mean and std of sample point generated by hspice2012 is 0 and 1/3.
I see the hspice user guild said agauss(0, 1, 3) means a gauss distribution which mean is 0 and std is 1/3.
So, what happens in hspice2021???
and the head of sample data generated by hspice2021 as follow:
$DATA1 SOURCE='PrimeSim HSPICE' VERSION='S-2021.09
$OPTION MEASFORM=1
$ This file format is subject to change
$ The seperator is
$index=1 is a nominal sample in Monte Carlo.
$option ignore_global_variation = no
$option ignore_local_variation = no
$option ignore_aging_variation = yes
$option ignore_interconnect_variation = no
$option ignore_spatial_variation = no
$option ignore_variation = no
$option sampling_method = srs
$option normal_limit = 20.0000
$option replicates = 1
$option random_generator = MCG
$option seed = 1
$option stream = 1
$option output_sigma_value = 1
$option use_agauss_format = yes
$option screening_method = pearson
$Global Variable number: 1
$Local Variable number: 0
$Aging Variable number: 0
$.TITLE 'four resistors
$.Option Sampling_Method = External Block_Name = extern_data
$.data extern_data
$ Column headers
$ Col Name and distribution data
$ 1 index
$ 2 globwidth
index globwidth