I tried passing variables to a gnuplot script as explained here, but I only get an error message:
Non-numeric string found where a numeric expression was expected
I am using gnuplot on Windows 7.
I had a friend try the same thing on Linux Mint and it works like a charm there.
Is this functionality just not included in the windows version of gnuplot or can I change something to accomplish the same thing? Is there another way to do this?
My script:
print "p0=$0 p1=$1 p2=$2 p3=$3 p4=$4 p5=$5 p6=$6 p7=x$7x"
How i call it:
gnuplot> call 'calltest.gp' "abcd" 1.2 + "'quoted'" -- "$2"
I use gnuplot Version 5.0 patchlevel 0.
The parameters to call must be strings. While conversion of numbers to strings works on Linux, it makes problems on Windows:
Wrong:
call 'script.gp' 'string' 12
Correct:
call 'script.gp' 'string' '12'
You must also note, that the call behavior was changed with version 5. Now, ARG0 contains the naming of the called script, and the parameters are contained in variables ARG1, ARG2 etc.
Related
I have installed the Ruby environment manager rbenv, Ruby, RubyGems, and PNGlitch (on macOS). Now how do I use PNGlitch?
The best documentation I have been able to find is on this page, and here's an example of the syntax given:
How to use this library: The Simple Way
png = PNGlitch.open '/path/to/your/image.png'
png.glitch do |data|
data.gsub /\d/, 'x'
end
png.save '/path/to/broken/image.png'
png.close
Okay, great. When I insert my file paths, save that code as an .rb file, and open it, I just get:
test.rb: command not found
If I paste it directly into Terminal I get:
png = PNGlitch.open '/Users/username/Documents/testimage.png'
-bash: png: command not found
ComputerName:~ username$ png.glitch do |data|
> data.gsub /\d/, 'x'
-bash: png.glitch: command not found
-bash: data: command not found
-bash: data.gsub: command not found
ComputerName:~ username$ end
-bash: end: command not found
ComputerName:~ username$ png.save '/Users/username/Documents/testimage_glitched.png'
-bash: png.save: command not found
ComputerName:~ username$ png.close
I also tried the syntax given on this page and entered:
pnglitch /Users/username/Documents/testimage.png –filter=Sub /Users/username/Documents/testimage_glitched.png
...this resulted in getting the following message:
tried to create Proc object without a block
Usage:
pnglitch <infile> [--filter=<n>] <outfile>
Options:
-f, --filter=<n> Fix all filter types as passed value before glitching.
A number (0..4) or a type name (none|sub|up|average|paeth).
--version Show version.
-h, --help Show this screen.
↑ I guess this is the developer's idea of documentation. 🤣
Well, trying to follow that example I also did this:
pnglitch </Users/username/Documents/testimage.png> [--filter=<2>] </Users/username/Documents/testimage_glitched.png>
...but that only resulted in:
-bash: syntax error near unexpected token 2
(I chose 2 because apparently that corresponds to the "Sub" filter.)
I tried variants of this syntax as well, including omitting characters <> and [].
There must be some assumed knowledge here that I don't have. So what I would like to know is:
How can I actually use PNGlitch to glitch a PNG image?
How can I use PNGlitch to glitch all the PNG images in a folder?
Any additional advice on using different filters would also be appreciated.
Thank you.
There's a lot going on here that needs to be cleared up.
Ruby scripts need Ruby to run
You can't just paste these into bash and expect anything useful to happen.
The usual procedure is one of two variants. Either:
Create a .rb script, like example.rb
Run ruby example.rb where that's your script name at the end.
Or use the "hash-bang" method:
Create a script with #!/usr/bin/env ruby as the very first line.
Make this script executable with chmod +x example.rb
Run this script directly, ./example.rb or whatever path it has.
Note that example.rb by itself will not work unless it is in your path, hence the ./ is necessary.
Command line example syntax
Here <name> has special meaning, where it's just a way of saying name as if it had italics or special formatting. On a text-mode terminal it's not practical to add syntax like that, it's limited to ASCII in most cases, so this tradition evolved.
Within the POSIX shell > and < have special meaning, they're used to, respectively, redirect input to or from a file. For example, ls > ls.txt dumps the output of ls into a file called ls.txt, while cat < ls.txt reads in the contents of ls.txt and displays it.
Things like [name] mean optional arguments, like [--help] means the --help argument is optional.
Within the POSIX shell [ and ] have special meaning. They can be used in an if construct, but more commonly in file wildcards, like l[abc].txt means any of la.txt, lb.txt or lc.txt.
Putting this together it's possible to understand the notation used here:
pnglitch <infile> [--filter=<n>] <outfile>
Where that means infile is your "input file" argument, and outfile is your "output file" argument, and --filter is an optional argument taking n as an input.
So you call it like this:
pnglitch input.png output.png
Or with an option, like you did:
pnglitch testimage.png --filter=sub testimage_glitched.png
Though note I've used lower-case sub as that's precisely what's in the help output and following casing conventions usually matters.
In an Applescript I am trying to pass on a URL that I receive as an argument to a do shell script command to use it with curl.
With regular characters the procedure works fine, but as soon as my argument contains special characters like Umlauts, it gets all funky.
curl does download something, but replaces the letter Ü with à etc., which of course will not get me the correct result.
What do I need to do, to get this to work? I am neither very skilled with Applescript nor with encoding issues.
My setup at the moment is as follows:
set download_URL to item 1 of arguments
do shell script "curl " & download_URL & " > targetFile.html"
Some examples of what happens:
Äquivozität ---> Ãquivozität
Ökolikör ---> Ãkolikör
Übermütigkeit ---> Ãbermütigkeit
Schweißfuß ---> SchweiÃfuÃ
Which makes my confusion even greater. All Ä, Ö, Ü and ß render as Ã, but both in the editing mask here and in the one of the site in question they render as shown in this image.
Also, through some amateurish digging in the html-File, I figured out that instead of the letter Ü, I would need to pass the letters %C3%9C. So the whole procedure does work, if I pass %C3%9Cbermut instead of Übermut. However, I would of course like to avoid creating a translation table for all diacritics.
Can somebody figure out, what specific encoding problem is happening here?
After some more researching, I found out that what I need to urlEncode my string. That way, the letter Ü will be replaced with %C3%9C and it works for my purposes.
Applescript does not seem to support this natively, but one can use php to do the conversion. I found the method here: https://discussions.apple.com/message/9801376#9801376
So, in my case I used it like this:
set keyword to item 1 of arguments
set encodedKeyword to do shell script "php -r 'echo trim(urlencode(" & "\"" & keyword & "" & "\"));'"
do shell script "curl https://www.myUrl.com/" & encodedKeyword & ".html > targetFile"
This way, it works for me.
In case there is a better way - maybe something that works in Applescript directly - feel free to post another answer, then I'll change the accepted answer.
I'd like to know how to pass arguments to a golfscript program from the command line. I'm using ruby interpreter that I downloaded from golfscript.com. From what I understood from googling a bit, in ruby you pass arguments like this ruby ./program.rb 4, but doing ruby ./golfscript.rb prnt.gs 4 doesn't work (prints an empty string).
In golfscript the arguments are supposed to be made into a string and pushed to the stack.
prnt.gs's code is just p (it's supposed to print the top of the stack - the argument).
What am I doing wrong?
try running it like this:
>echo 4 | ruby golfscript.rb prnt.gs
I'm trying to use system to run nmap from a ruby program. I want to escape some of the arguments to prevent shell injection so I'm using the following form:
system('nmap', '-sn', hostname)
This works fine, however I want to use the -oX - option to output xml to stdout. The following code doesn't seem to work though:
system('nmap', '-sn', '-oX -', hostname)
The -oX - argument seems to be ignored, can anyone suggest a workaround?
As system also escapes spaces in arguments, your system call with -oX - will effectively be called as
nmap "-sn" "-oX -" "example.com"
with the space being part of a single argument. It will thus not be considered a valid argument for nmap. To fix this, you actually have to pass it as two arguments. Here, the space in the single argument will not be escaped:
system('nmap', '-sn', '-oX', '-', hostname)
I'm trying to create a mask and use the bitwise operator "&" to compare to another variable and see the output. Let there be code:
mask=00000
mesk=00010
mosk=$mask&$mesk
echo $mosk
echo meec
I'm trying to expand this functionality to be able to have more characters (different error/success codes), but those lines just don't work: Executing the script will print an empty line, then "meec".
I came from an object oriented programming background, and although I've read through several documents on this subject, it seems there's something I'm missing.
Any help would be appreciated.
Edit: For some reason, turns out the code doesn't work, it says "command 00010 not found" >_>
It's because usually the & character in the shell is the modifier to put a command in the background.
You have to use Arithmetic Expansion of Bash (for example) for it to work:
mosk=$(($mask & $mesk))