Tags: 123srand, argument, claimes, clicks, clock, expr, floating-point, milliseconds, programming, srand, tcl, value

srand() claimes to get a floating-point value from "clock clicks"?

On Programmer » TCL

2,516 words with 2 Comments; publish: Wed, 07 May 2008 10:05:00 GMT; (20046.88, « »)

Hello,

something I don't really understand:

% expr {srand([clock milliseconds])}

can't use floating-point value as argument to srand

% expr {srand([clock microseconds])}

can't use floating-point value as argument to srand

% expr {srand([clock clicks])}

can't use floating-point value as argument to srand

% expr {srand(wide([clock clicks]))}

can't use floating-point value as argument to srand

% expr {srand(int([clock clicks]))}

0.8654289347424307

% expr {srand([clock seconds])}

0.1414733348141766

Is there still some work to be done to make the math functions support

wide integers?

I assume this because of the same error message, when using the wide()

conversion.

Should I file a bug?

Best regards,

Martin Lemburg

UGS - Transforming the Process of Innovation

All Comments

Leave a comment...

  • 2 Comments
    • MartinLemburg.tcl-program.itags.org.UGS wrote:

      > % expr {srand([clock milliseconds])}

      > can't use floating-point value as argument to srand

      Upgrade to CVS sources (or maybe the most recent ActiveTcl?)

      to get an improved error message:

      % expr {srand([clock milliseconds])}

      integer value too large to represent

      The srand() function accepts only those values that pass

      [string is integer]:

      % string is integer [clock milliseconds]

      0

      That is, only values that fit in the C "long" type are acceptable.

      This has always been the case with the srand() function.

      > Should I file a bug?

      You might file a request to truncate larger integers to the "long"

      range instead of throwing an error. Compatibility considerations

      would have to be looked into.

      | Don Porter Mathematical and Computational Sciences Division |

      | donald.porter.tcl-program.itags.org.nist.gov Information Technology Laboratory |

      | http://math.nist.gov/~DPorter/ NIST |

      |_______________________________________

      _______________________________|

      #1; Wed, 07 May 2008 10:06:00 GMT
    • Hi Don,

      I tested this with a tclkit of the tcl version 8.5a4.

      Yes, I would like to suggest an automatic truncation to a long value or

      if not possible a better error message! ;-)

      So I'll do the next days on sourceforge.net.

      Nice wend!

      Martin Lemburg

      UGS - Transforming the Process of Innovation

      #2; Wed, 07 May 2008 10:07:00 GMT