Standard Normal random numbers between -4 and 4

Script

#10 sets of 1000 random variables
source randFreq.tcl;
#reading csv file:"dataSample_Normal.csv"
set L [::randFreq::loadFile ./dataSample_Normal.csv , utf-8];
::randFreq::outputFreq $L ,;
#=== frequency class range ===
#between -4.0 and 4.0 with step 0.1

dataSample_Normal.csv

Output file: 1515918006dataFreq.txt

10_datasets
variables,averages,standard_deviations
-4.0000,0.0,0.0
-3.9000,0.0,0.0
-3.8000,0.1,0.31622776601683794
...
3.5000,0.1,0.31622776601683794
3.6000,0.1,0.31622776601683794
3.7000,0.1,0.31622776601683794
3.8000,0.0,0.0
3.9000,0.0,0.0
4.0000,0.0,0.0

Output results shown in a graph