Instruction on how to set up Jython in weka, especially on setting Environment variable for accessing dataset files, made it clear and easy for windows user, but no information was given for Mac user.
I wonder how to set up Environment variable in Mac for Jython in weka to work.
Solution
After the installation of Jython and JFreeChart library from Weka Package manager;
go to home directory's terminal, enter nano .bash_profile
inside .bash_profile, add a line of code as below
export Weka_Data=User/Documents/Directory/Of/Your/Data
save and exit
inside terminal run source .bash_profile
Now, Environment variable for Jython in weka to access dataset is all set.
Related
I am trying to add to the PATH via the Environment Variable settings windows for python.exe.
I have read the instructions using SetX from the March 3, 2012 discussion about this issue and am worried I will make a mess of my machine, so want to stick with the GUI process.
The directory path is C:\Users\Paul\AppData\Local\Programs\Python\Python37\python.exe.
That is a copy from the addition I made in the System Variables section of the Environment Variables window.
I have labelled the Variable Name as "Python", no quotation marks.
I have checked the path, and it looks good to me, and have rebooted the computer. But I still get the
'python.exe' is not recognized as an internal or external command, operable program or batch file.' error in every directory expect if I am specifically in the Python37 directory.
Any idea what I am doing wrong?
The path environment variable contains one or more paths, separated by semicolons. When you try to execute a command in cmd.exe it checks each path listed in the path variable in order of first to last until it finds the executable or runs out of paths to check.
You can experiment without making permanent changes to your system first. Run cmd.exe and type
set path=%path%;C:\Users\Paul\AppData\Local\Programs\Python\Python37
Running python.exe should now work in any directory in this cmd.exe window.
Unlike other environment variables, path is special and is a merged value from the system and user variables. Since you installed python just for yourself you might as well just use a user variable.
In the system properties where you edit environment variables, if there is no path user variable, create one and set it to C:\Users\Paul\AppData\Local\Programs\Python\Python37 or if it already exists, append ;C:\Users\Paul\AppData\Local\Programs\Python\Python37.
In newer versions of Windows 10 the UI is different and you don't have to add the semicolon because it lets you edit them as separate entries.
I previously asked a similar question with regards to cloud9, but I am now trying to do the same project in parallel on my windows 10 machine because I will not have internet access to use cloud9. I am trying to set up the configuration in preparation for following Daniel Kehoe's learn-rails tutorial book, but I am having trouble setting up the environment variables. The book seems to explain how to do it on Mac but I can not find the file in the atom editor. the book says to type the command:
atom ~/.bash_profile
However this just creates a new file that is not part of my rails app project directory. i have also tried
atom ~/.bashrc
which is the alternative but with the same result. It just creates a file unrelated to my project. The file is supposed to already exist somewhere.
I am supposed to put the environment variables into a file called ".bashrc" but I don't know where to find this file as it is hidden. How can I locate and open this file with Atom text editor?
.bashrc , .bash_profile are used in unix based operating systems for the terminal. In windows you set environment variables differently. In windows 10, search for environment variables in start menu, and select Edit the system environment variables and set them from there.
PS: You can have .bashrc if you have installed something like git bash, cygwin bash or bash for windows 10 or something else. And all 3 handle .bashrc differently.
Typing echo ~ in the Git Bash terminal will tell you where that folder is which contains the .bashrc file
I was watching the Android development video and they asked us to install JDK and create JAVA_HOME environment variable.
I already have MyEclipse installed and I previously had setup the PATH variable(giving it the directory of JDK), do I still need a JAVA_HOME variable ??? If yes then why ???
Yes, you do need.
PATH is usually used to lookup the executables so that you haven't to specify the whole path to execute. JAVA_HOME may be used by the scripts or IDEs to lookup libraries. You can specify JAVA_HOME and build path variable basing on it. E.g (depending on OS)
PATH=$PATH;$JAVA_HOME/bin
Short answer, YES, you do need to set JAVA_HOME.
You can read here the difference between each one of them, but I'm pasting the explanations below as well:
JAVA_HOME and JRE_HOME are not used by Java itself. Some third-party programs (for example Apache Tomcat) expect one of these environment variables to be set to the installation directory of the JDK or JRE. If you are not using software that requires them, you do not need to set JAVA_HOME and JRE_HOME.
CLASSPATH is an environment variable which contains a list of directories and / or JAR files, which Java will look through when it searches for Java classes to load. You do not normally need to set the CLASSPATH environment variable. Instead of using this environment variable, you can use the -cp or -classpath option on the command line when using the javac and java commands.
PATH is an environment variable used by the operating system (Windows, Mac OS X, Linux) where it will look for native executable programs to run. You should add the bin subdirectory of your JDK installation directory to the PATH, so that you can use the javac and java commands and other JDK tools in a command prompt window. The JDK installation instructions explain how to set PATH.
If the application you are using is looking for a specific dataset in the JAVA_HOME environment variable and it isn't there, it is not going to be happy.
Other applications might look for the JDK path in the PATH environment variable, but just because you have it there doesn't mean it will work for other applications that need it in a separate variable.
When I run targets on ant it says it is unable to locate the variable I passed to it.
Config for environment variables :
in build.xml
<property environment="Env"/>
but I am unable to find the parameter defined parameter with
${Env.CATALINA_HOME}
where in the .bash_profile
export CATALINA_HOME=/Users/olgunkaya/development/apache-tomcat-7.0.34
and export PATH=${PATH}:$CATALINA_HOME
What can I do to achive this ?
Before you run ant, check to see if CATALINA_HOME is actually defined as an environment variable. I bet you'll find it isn't. Ant doesn't read your .profile or .bash_profile before starting, so if it's not already defined in your environment, Ant won't see it.
As you've seen opening a terminal window on a Mac doesn't necessarily guarantee that the .bash_profile file is executed. Try setting up these environment variables in .bashrc file instead.
Or, you can force .bash_profile to run by setting it as the Startup file in Terminal. Select File->Preferences from the menu, go to the Shell tab, select your default shell, and then click the Run Command checkbox and put .bash_profile in there. That will guarantee that .bash_profile is executed with each new terminal window.
I had a similar problem when referencing a custom variable, which was definitely defined in the shell spawning ant.
The solution was to EXPORT the variable when defined (in ~/.profile), so the shell would pass it to its children.
I see that $JAVA_HOME is a built-in variable in IzPack. Can I assign to it in a pre-install script and have the installer use that? Currently I am stuck on a machine that defaults to an open-source JRE that runs horribly and I need to reassign it to the Sun JRE so that the installer will run properly.
In the pre-install script, can I append to the $PATH with:
${ENV[PATH]} = ${ENV[PATH]}:/usr/local/java/bin
Let me know what I can do, I cannot get access to write to the .cshrc or .cshrc.login and I cannot tell my users to set the environment variables themselves.
The answer to this for me was that I had to write a python script that set the environment variables and then called a subprocess to launch the installer. This is far from ideal, but it seems like if your machine is stuck by default with an open source JRE, then you can't fix that any other way.