# Program correction

**URL:** <http://discourse.iapct.org/t/program-correction/9152>\
**Category:** CSG1995\
**Created:** [September 13, 1995, 8:23pm UTC](http://discourse.iapct.org/t/program-correction/9152 "1995-09-13T20:23:59Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![William\_T\_Powers4](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/w/977dab/32.png) [@William\_T\_Powers4](http://discourse.iapct.org/u/William_T_Powers4)\
**Post date:** [September 13, 1995, 8:23pm UTC](http://discourse.iapct.org/t/program-correction/9152/1 "1995-09-13T20:23:59Z")

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[From Bill Powers (950913.1415 MDT)]

Slight error in the program I posted earlier. The first line of code in  
the dist function has an extra term that got put in by a cosmic ray  
(determined after extensive research). The function should read

function dist: real;  
begin  
x1 := 10000.0\*(random - 0.5);  
x2 := x2 + slow \* (x1 - x2);  
x3 := x3 + slow \* (x2 - x3);  
dist := x3;  
end;

For some reason taking it out made the RMS errors larger than before for  
smaller values of the slowing factor (possibly due to rounding errors in  
adjusting the table for zero average and 1000 max value):

Slowing = 0.01 RMS ERROR = 5.5  
Slowing = 0.02 RMS ERROR = 11.0  
Slowing = 0.03 RMS ERROR = 15.9  
Slowing = 0.04 RMS ERROR = 17.9  
Slowing = 0.05 RMS ERROR = 23.2  
Slowing = 0.06 RMS ERROR = 25.7  
Slowing = 0.07 RMS ERROR = 31.8  
Slowing = 0.08 RMS ERROR = 36.2  
Slowing = 0.09 RMS ERROR = 37.8  
Slowing = 0.10 RMS ERROR = 42.9  
Slowing = 0.11 RMS ERROR = 48.7  
Slowing = 0.12 RMS ERROR = 52.1  
Slowing = 0.13 RMS ERROR = 59.6  
Slowing = 0.14 RMS ERROR = 58.1  
Slowing = 0.15 RMS ERROR = 66.1  
Slowing = 0.16 RMS ERROR = 70.9  
Slowing = 0.17 RMS ERROR = 66.9  
Slowing = 0.18 RMS ERROR = 80.7  
Slowing = 0.19 RMS ERROR = 82.9  
Slowing = 0.20 RMS ERROR = 86.4

> **···**
>
> -----------------------------------------------------------------------  
> Best,
> 
> Bill P.