Re: wrong result for exponecial density distribution?

[Jaroslav Hajek]

On Tue, Mar 18, 2008 at 8:47 PM, aircat <address@hidden> wrote:
> Bug report for Octave 2.9.19 configured for i486-pc-linux-gnu
>
>  Description:
>  -----------
>
>   *     I found a wrong result for exponecial density distribution
>         The two traces i send must be the same, I also checked with trace on
>  wikipedia
>         http://en.wikipedia.org/wiki/Exponential_distribution
>


Octave's exppdf uses the form found in the above article as "alternate
parameterization".
However, I think that for clarity the documentation can be slightly adjusted.
A changeset is attached.

>  Repeat-By:
>  ---------
>
>   *     octave:141> subplot(211)
>         octave:142> x=[0:.1:5];plot(x,exppdf(x,0.5));
>         octave:143> subplot(212)
>         octave:144> x=[0:.1:5];plot(x,0.5*exp(-0.5.*x));
>
>
>
>




>  Configuration (please do not edit this section):
>  -----------------------------------------------
>
>  uname output:     Linux sysName 2.6.18-5-686 #1 SMP Wed Oct 3 00:12:50
>  UTC 2007 i686 GNU/Linux
>  configure opts:   '--prefix=/usr' '--datadir=/usr/share'
>  '--libdir=/usr/lib' '--libexecdir=/usr/lib' '--infodir=/usr/share/info'
>  '--mandir=/usr/share/man' '--with-blas=-lblas-3'
>  '--with-lapack=-llapack-3' '--with-hdf5' '--with-fftw'
>  '--with-f77=/usr/bin/g77' '--enable-shared' '--enable-rpath'
>  '--disable-static' '--build' 'i486-linux-gnu'
>  'build_alias=i486-linux-gnu' 'CC=/usr/bin/gcc' 'CXX=/usr/bin/g++'
>  'F77=/usr/bin/g77'
>  Fortran compiler: /usr/bin/g77
>  FFLAGS:           -O2
>  F2C:              @F2C@
>  F2CFLAGS:         @F2CFLAGS@
>  FLIBS:            -L/usr/lib/gcc/i486-linux-gnu/3.4.6
>  -L/usr/lib/gcc/i486-linux-gnu/3.4.6/../../../../lib
>  -L/usr/lib/gcc/i486-linux-gnu/3.4.6/../../.. -L/lib/../lib
>  -L/usr/lib/../lib -lhdf5 -lz -lfrtbegin -lg2c -lm
>  CPPFLAGS:
>  INCFLAGS:         -I. -I. -I./liboctave -I./src -I./libcruft/misc
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>  (Debian 4.2.2-4)
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>  LEXLIB:
>  LIBGLOB:
>  SED:              /bin/sed
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>
>  User-preferences (please do not edit this section):
>  --------------------------------------------------
>
>   EDITOR = emacs
>   EXEC_PATH =
>  
> /usr/lib/octave/2.9.19/site/exec/i486-pc-linux-gnu:/usr/lib/octave/api-v31/site/exec/i486-pc-linux-gnu:/usr/lib/octave/site/exec/i486-pc-linux-gnu:/usr/lib/octave/2.9.19/exec/i486-pc-linux-gnu:/usr/bin:/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games
>   IMAGE_PATH = .:/usr/share/octave/2.9.19/imagelib
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>
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>   gnuplot_command_with = w
>   history_file = /home/userName/.octave_hist
>   history_size = 1024
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>   split_long_rows = 1
>   string_fill_char =
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>   suppress_verbose_help_message = 0
>
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>



-- 
RNDr. Jaroslav Hajek
computing expert
Aeronautical Research and Test Institute (VZLU)
Prague, Czech Republic
url: www.highegg.matfyz.cz

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