March 6, 2024: Dwarf Fortress 50.12 has been released.
News: February 3, 2024: The February '24 Report is up.
News: February 4, 2021: Dwarf Fortress Talk #28 has been posted.
News: November 21, 2018: A new Threetoe story has been posted.
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https://hardware.slashdot.org/story/16/10/18/194231/co2-to-ethanol-in-one-step-with-cheap-catalyst
Here's a happy one though. Oak Ridge National Laboratory have discovered a simple catalyst to turn CO2 + water directly into ethanol. And it's a government lab, so it won't be locked down with corporate patents.QuoteThe team used a catalyst made of carbon, copper and nitrogen and applied voltage to trigger a complicated chemical reaction that essentially reverses the combustion process. With the help of the nanotechnology-based catalyst which contains multiple reaction sites, the solution of carbon dioxide dissolved in water turned into ethanol with a yield of 63 percent. Typically, this type of electrochemical reaction results in a mix of several different products in small amounts. "We're taking carbon dioxide, a waste product of combustion, and we're pushing that combustion reaction backwards with very high selectivity to a useful fuel," Rondinone said. "Ethanol was a surprise -- it's extremely difficult to go straight from carbon dioxide to ethanol with a single catalyst."
Very nice stuff, the catalyst only uses common elements, it uses electricity (which could be from solar) to convert the CO2 directly into a usable alcohol. This could also compete against biofuels, which would reduce the pressure on farm lands while also reducing food price inflation. Turning CO2 from a waste product we can't get rid of, into a valuable commodity we use to make other things, is basically the holy grail.
Naming can be an issue for maintainability, but I mainly wanted to see evidence that you've acknowledged the core issue people brought up. I saw the renaming to "playerName" as not entirely conducive to believing you "got it".
As for remembering how to do things. Make program "templates" e.g. small programs/classes/functions that do that one thing as elegantly and generally as possible, in the least amount of code. Adhere to really clear naming conventions. Refer to those templates when you make new programs, classes or functions.
You're not expected to memorize boilerplate code. That's not how people operate. We have computers for that. The skill is to be able to see which chunk of boilerplate solution to apply where, then rename the "generic" names to specific names as needed (keep the generic names if it makes sense).
What 3man75 needs is a minimal example. I recently started learning Java and I used to have the same issue. It is possible to create one Scanner object and use that throughout the entire class to parse both strings and integers. Here is how I do that:Code: [Select]import java.util.Scanner;
public class InputManager
{
private Scanner input;
public InputManager()
{
// Create a single scanner for this class (private Scanner input;) and initialize it.
// You can create a new Scanner for each method, but it is easier to reuse this one.
input = new Scanner(System.in);
}
public void run()
{
System.out.println("Type a number to add one. Type a string to make it uppercase. Type 'exit' to quit.");
// Keep looping the program over and over until the user inputs 'exit'
while(true)
{
// Get whatever the user entered as a String. It *might* be a number
String command = input.nextLine();
// Exit the program for this special case
if(command.equals("exit"))
System.exit(1);
// This is a try-catch block. It is how Java does error handling.
// If something inside the try{} fails to work, it will send out an exception.
// If an exception is sent out, the program will skip to the catch{} part.
// If nothing fails and everything goes OK, the catch{} block will be ignored.
try
{
// Our command is a string. Try to turn it into an integer.
// If this part fails, the program will immediately go into the catch{} block.
int number = Integer.parseInt(command);
// If the user input something like '123' then the previous line worked.
// Since we turned the command into an integer, we can now add to it and print it.
System.out.println("Your input plus one: " + (number + 1));
}
catch(NumberFormatException e)
{
// If the program fails to turn the command into an integer, it will go here.
System.out.println("Your input converted to uppercase: " + command.toUpperCase());
}
}
}
}
If you want to test this code, you can run it in main like this:Code: [Select]public class InputTester
{
public static void main(String[] args)
{
InputManager test = new InputManager();
test.run();
}
}
~snip~
Ninja'd: Just why did you make a private scanner int all the way in the bottom? I've never seen that before.
I'm mention this because in previous programs he made a separate scanner for each input statement he wanted.
He named each of the scanners after the thing he was going to input. He's still using that naming convention, so I was skeptical as to whether he actually gets it.
EDIT: Nvm...I just changed it to make player name the only inputter. I'm not sure why I did this because it's been so long. Maybe I just forgot to change it.
But why are you naming your scanner after the variable you want to input? What would you do if you wanted to use scanners to input player name and player age? Can you demonstrate that? Then I'll show you what you're not understanding.
Yeah...EDIT: Nvm...I just changed it to make player name the only inputter. I'm not sure why I did this because it's been so long. Maybe I just forgot to change it.
But why are you naming your scanner after the variable you want to input? What would you do if you wanted to use scanners to input player name and player age? Can you demonstrate that? Then I'll show you what you're not understanding.
You do not need a duplicate Scanner. Like, ever. Or at least, I've never seen it.
I'm putting my foot down: you've been told on at least three occasions now about the duplicate Scanners thing. you need to fix that before I'd even consider having a look at the rest. And by "fix" I mean rewrite the program, then edit your existing post with the improved version. Don't spam additional posts with the same code, because that will just clutter the thread, modify the old post with any improvements.
If you ignored people about the scanners thing, how do I know that any advice I give you won't be ignored as well?
I seem to recall you saying something similar happened in your job: they got angry because you made the same mistake more than once. Be aware that you're doing the same thing to people in this thread. If you ever want a job as a programmer, they expect quick learners. The trick with being a so-called "quick learner" is to pay attention to what people tell you, then apply that. It's about actually paying attention to feedback.
-snip-
Sounds like your primary problem is trying to run before you can walk. That space marine program you're talking about seems far more complicated than a dice rolling program.
I am in a somewhat similar situation to you, so I'll share my advice based on my own experiences.
Biggest advice I'd give is: Start projects small, and build up from there. I'm creating simple programs to test concepts that I may want to later implement in a game. First I get the concept to work. Then I generalize it so it can work when moved to other programs, environments outside of the testing program written specifically for the concept. Then test those concepts later in a separate project, or add new features to old projects, or etc. All of this work ideally could then be used in the future in a larger, more complicated project, and at the same time I'm developing skill at programming and planning programs/algorithms and debugging and etc, and those skills would definitely be useful for later more complicated projects.
edit: Ninja'd by Reelya, who said what I was trying to but in less words.
