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Install Unique Package

da bearsNov 13 2021

Machine: GPU 3.1
Shape: Linux 8 GPU
Thank you to anyone who attempts to help. I've created an instance and logged into it. Before running the code, I have to install a handful of packages. Looking at several tutorials I take the following steps:
I) sudo dnf module install python39
II) sudo dnf install python39-pip
III) python3.9 -m install -r requirement.txt
We should be cooking with fire now(!) But one of the libraries (called "norse") is failing upon installation due to a PEP 500 error. Previously, I ran into issues with this library on another machine and had to install it on a virtual environment with the following code:
$ module load gcc-9.2
$ mkdir ~/envs
$ virtualenv3.9 ~/envs/norse
$ source ~/envs/norse/bin/activate
(norse) $ pip install -U norse

Unfortunately, I've tried to load gcc-9.2, but run into an error:
Screen Shot 2021-11-13 at 3.11.29 PM.pngI'm looking for guidance. I believe that the right way to go about my issue is to create a virtual environment and download all of my packages there, but if there is another way then I'm all ears (my instance name opc@success was not aptly chosen). Thank you again!

This post has been answered by da bears on Nov 17 2021
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Comments

843793
Well, this was a shot in the dark, but I tested it and it seems to be the problem: remove the parens around i.next()!

After doing so, running the code in your post instead provides a "NoSuchElementException" from the iterator (completely expected). I'm not sure if this a bug in the compiler, or if it has something to do with the way the code gets expanded. Maybe if someone thinks about it long enough they'll be able to come up with a reason.
843793
Why would you expect to use those parens like that anyway?
843793
Why would you expect to use those parens like that
anyway?
I can see that the parens are redundant - and as the other responder pointed out, the error goes away when they are removed...however, I'm still curious...

Firstly, is it actually an error to use the parentheses in that way?

Secondly, although the offending line is executed in the example I gave, the code that I pulled the example from is a bit stranger - when I try to instantiate a class (call it B), that contains a method with the redundant parentheses, I get the same error - even though the offending line isn't executed (I can post the code tonight if anyone is interested).

Gareth
843793
Here's the code:

import java.util.*;
class A {
public static void main (String argv[]) {
B bb = new B();
}
}

class B {

void methodC() {
ArrayList<Boolean> B = new ArrayList<Boolean>(10);
Iterator<Boolean> i = B.iterator();
boolean b = (i.next()).booleanValue();
}
}

843793
This is definitely a bug in the compiler. The bytecode generated for B.methodC() is:

Codeview "bytecode" for void B.methodC():
#3/Test.java:12 - new class java.util.ArrayList
#4/Test.java:12 - dup
#5/Test.java:12 - bipush (byte)10
#6/Test.java:12 - invokespecial public java.util.ArrayList(int)
#7/Test.java:12 - astore_1 lv_1
#8/Test.java:13 - aload_1 lv_1
#9/Test.java:13 - invokevirtual public java.util.Iterator java.util.AbstractList.iterator()
#10/Test.java:13 - astore_2 lv_2
#11/Test.java:14 - aload_2 lv_2
#12/Test.java:14 - invokeinterface public abstract java.lang.Object java.util.Iterator.next()
#13/Test.java:14 - invokevirtual public final boolean java.lang.Boolean.booleanValue()
#14/Test.java:14 - istore_3 lv_3
#15/Test.java:15 - return

and it's clear that between instruction #12 and instruction #14 a typecast is missing.

I'll add this to my list of known prototype compiler bugs at
http://cag.lcs.mit.edu/~cananian/Projects/GJ/
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Added on Nov 13 2021
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