Data update

Task/Random-numbers/DuckDB/random-numbers.duckdb

@@ -0,0 +1,14 @@
+# The Box-Muller method
+create or replace function rnv(mean, sd, u, v) as
+  (select ( sqrt(-2 * ln(u)) * cos(2 * pi() * v) * sd) + mean);
+
+create or replace table t as
+  (with rows as (select random() as u, random() as v from unnest(range(0,1000)))
+   select rnv(0, 0.5, u, v) as rnv from rows);
+
+from t limit 5;
+
+select avg(rnv) as average,
+       stddev_samp(rnv) as 'sample stddev',
+       stddev_pop(rnv) as 'population stddev'
+from t;

Task/Random-numbers/REXX/random-numbers.rexx

@@ -1,4 +1,4 @@
--- 8 May 2025
+-- 28 Jul 2025
 include Settings
 
 say 'RANDOM NUMBERS'
@@ -19,53 +19,53 @@ call Timer
 exit
 
 GetUniform:
-procedure expose glob. work.
+procedure expose Memo. Work.
 arg xx
 say 'Get' xx 'uniform distributed Random numbers...'
-work. = 0
+Work. = 0
 do n = 1 to xx
-   work.n = Randu()
+   Work.n = Randu()
 end
-work.0 = xx
+Work.0 = xx
 say 'Done'
 say
 return
 
 GetNormal:
-procedure expose glob. work.
+procedure expose Memo. Work.
 arg xx
 say 'Get' xx 'normal(1,1/2) distributed Random numbers...'
-work. = 0
+Work. = 0
 do n = 1 to xx
-   work.n = Randn(1,0.5)
+   Work.n = Randn(1,0.5)
 end
-work.0 = xx
+Work.0 = xx
 say 'Done'
 say
 return
 
 ShowFirst:
-procedure expose work.
+procedure expose Work.
 say 'First 5 items...'
 do i = 1 to 5
-   call CharOut ,work.i/1' '
+   call CharOut ,Work.i/1' '
 end
 say; say
 return
 
 ShowStats:
-procedure expose work.
-say 'Statistics for' work.0 'items...'
+procedure expose Memo. Work.
+say 'Statistics for' Work.0 'items...'
 sum = 0
-do n = 1 to work.0
-   sum = sum+work.n
+do n = 1 to Work.0
+   sum = sum+Work.n
 end
-avg = sum/work.0
+avg = sum/Work.0
 sum = 0
-do n = 1 to work.0
-   sum = sum+(work.n-avg)**2
+do n = 1 to Work.0
+   sum = sum+(Work.n-avg)**2
 end
-varia = sum/work.0; stdev = SqRt(varia)/1
+varia = sum/Work.0; stdev = SqRt(varia)/1
 say 'Average  ' Std(avg)
 say 'Deviation' Std(stdev)
 say 'Variance ' Std(varia)
@@ -73,7 +73,7 @@ say
 return
 
 ShowExact:
-procedure expose work.
+procedure expose Memo.
 say 'Exact statistics for infinite items...'
 say 'Average  ' 1/2 '(1/2)'
 say 'Deviation' Std(SqRt(1/12)) '(SqRt(1/12))'
@@ -81,7 +81,4 @@ say 'Variance ' 1/12 '(1/12)'
 say
 return
 
-include Functions
-include Constants
-include Helper
-include Abend
+include Math