Why did u put the Xlate inside a for loop??
The Xlate *will* loop every char in the str parm
Remove the For/EndFor and time test it again
-----Original Message-----
From: RPG400-L <rpg400-l-bounces@xxxxxxxxxxxxxxxxxx> On Behalf Of Jon Paris
Sent: Friday, November 19, 2021 11:18
To: RPG programming on IBM i <rpg400-l@xxxxxxxxxxxxxxxxxx>
Subject: Re: [EXTERNAL] Remove unprintable chars
My first thought was the same as Bruce's - that an individual character loop would be by far the fastest approach.
You always have to remember that no magic is involved and that in order to implement %Xlate or %ScanRpl RPG still has to implement a character at a time loop unless there is can underlying system function that can perform the task - and even then that just moves that loop down closer to the hardware.
But so many in this thread seemed convinced that the BIF approach would be faster I decided to test and compare Francois' code with a simple loop.
The time difference is dramatic. The single char loop is orders of magnitude faster.
Run the following and see for yourself. On my system I get the following:
DSPLY Xlate took: 1094
DSPLY Loop took: 59
And those results are consistent.
Here's the code I used - if you spot a bug let me know.
**free
dcl-ds str;
strChar char(1) Dim(1000);
end-ds;
dcl-s blank64 char(64) inz;
dcl-s i int(5);
dcl-s startTime timestamp;
dcl-s endTime timestamp;
startTime = %timestamp();
for i = 1 to %elem(strChar);
str = X'12' + 'some string' +X'350A13';
str = %Xlate(X'000102030405060708090A0B0C0D0E0F+
101112131415161718191A1B1C1D1E1F+
202122232425262728292A2B2C2D2E2F+
303132333435363738393A3B3C3D3E3F'
: blank64
:str);
endfor;
endTime = %timestamp();
Dsply ( 'Xlate took: ' + %char(%diff( endTime : startTime : *MS )));
startTime = %timestamp();
for i = 1 to %elem(strChar);
if strChar(i) < X'40';
strChar(i) = *Blank;
endif;
endfor;
endTime = %timestamp();
Dsply ( 'Loop took: ' + %char(%diff( endTime : startTime : *MS )));
*InLr = *On;
On Nov 18, 2021, at 6:45 PM, Francois Lavoie <Francois.Lavoie@xxxxxxxxxxxxxxxxxxxx> wrote:
Here's the code I tested: ultra fast and ultra compact. A 1-liner
beats any slow do 1-char at a time multi-line of code loop dcl-s str
char(1000);
str=X'12'+'some string'+X'350A13';
str=%Xlate(X'000102030405060708090A0B0C0D0E0F+
101112131415161718191A1B1C1D1E1F+
202122232425262728292A2B2C2D2E2F+
303132333435363738393A3B3C3D3E3F'
:' '+
' '
:str);
make sure the 2nd parm of the Xlate bif has exactly 64 blanks
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