Doubts on scripting: error messages when trying to run and how to process lots of files

Question

I have created my first mathematica 'program' as I think of it, to do some image processing. After reading in an image, it does a lot of stuff (including smoothing, fourier transform, functional representation, searching for critical points, outputing various files).

Now, I have hundreds of images that I want to process: obviously a job for a script. But I am somehow not understanding the whole mess of CommandLine, ScriptCommandline, or even how to properly edit script files (am I supposed to do it in the notebook? Because I'm using a lot of mathematica symbols, so I'm not sure how I could edit otherwise) or how to get scripts to run! It seems part of the problem is that scripting has changed in Mathematica 9 and a lot of previous Q&A entries focus on solutions for prior versions.

I have tried to get a basic script working on my system and I get really odd errors. E.g.,

#!/Applications/Mathematica.app/Contents/MacOS/MathematicaScript - script

(*generate "num" samples of a mixed distribution*)

num = ToExpression[$ScriptCommandLine[[2]]];
Print /@ RandomVariate[
  MixtureDistribution[{1, 2}, {NormalDistribution[1, 0.2], 
    NormalDistribution[3, 0.1]}], num, WorkingPrecision -> 50]

I get:

$ ./test.m 10

./test.m: line 1: F814W_knotD_ACSHRC_2.91772_J8L001031_50_.fits: command not found

./test.m: line 3: F814W_knotD_ACSHRC_2.91772_J8L001031_50_.fits: command not found

./test.m: line 4: *#!/Applications/Mathematica.app/Contents/MacOS/MathematicaScript: No such file or directory

./test.m: line 5: F814W_knotD_ACSHRC_2.91772_J8L001031_50_.fits: command not found

./test.m: line 6: syntax error near unexpected token `*generate'

./test.m: line 6: `(*(generate "num" samples of a mixed distribution)*)'

(those fits files are in the same directory, and I have NO IDEA why it is talking about them)

Apologies for the newbie questions... hopefully this will be the last one for a while!!

Answer 1

Running this script (using the command line ./m.m 10):

#!/Applications/Mathematica.app/Contents/MacOS/MathematicaScript -script

Print["$CommandLine ",$CommandLine]
Print["$ScriptCommandLine ",$ScriptCommandLine]

num  = ToExpression[$ScriptCommandLine[[2]]];
Print /@ RandomVariate[
  MixtureDistribution[ 
    {1, 2},
    {NormalDistribution[1, 0.2],
     NormalDistribution[3, 0.1]}
  ], num,  WorkingPrecision -> 50]

produces this output:

"$CommandLine "{"/Applications/Mathematica.app/Contents/MacOS/MathKernel",
    "-runfirst", "$TopDirectory=\"/Applications/Mathematica.app\"",
    "-script", "./m.m", "--", "./m.m", "10"}

"$ScriptCommandLine "{"./m.m", "10"}

RandomVariate::precw: The precision of the argument function (0.2) is less than WorkingPrecision (50.).    
RandomVariate::precw: The precision of the argument function (0.1) is less than WorkingPrecision (50.).
0.92362819946979828682106332648179186999782644688375288593250014006949862225735`50.
2.96103460393397517361865538246094728357244256713761606288848501196722308810617`50.
3.22939297821123529215296685035285675313397350043182381985784401189668224360831`50.
1.1299906869216789003021775704042950015847131552578997137000319851764860372795`50.
0.98372766259941810455456369928428955216530068876264782478190250513548418549102`50.
2.99474740714212023905930071261105968607684691113025981921878898633890621560002`50.
3.08308256890408917851510742142231108891166198857011370317940248018144299347434`50.
2.90810822969521393130661661374500034380445967807811953513718200317327510030055`50.
1.10703367896318353371179385146615947292441105821579138236874372016639707194483`50.
3.08119877332762386092842323142602437311553703195855620999359603331598402631764`50.

Your example had a space between - and script; that may be the problem, although when I tried it with a space the errors were different from yours.

I'm on Mac OSX, Mathematica version 9.