perl programming(quite similar to java)

[monk23785]

I'm currently doing perl programming as part of my chemistry course and so far its been pretty similar to java so maybe someone can help me with this.

How can you return/print the number of an array, not the actual value thats in the array but the array numbers itself(eg 0, 1,2, 3, 4 etc)

Its just a little task we've been given but its bugging me that i can't do it

[krashd]

not a clue, if you were in dundee you could go to the balcony and ask for Ken, he's a Perl whizzkid.

chemistry teaching perl? curious.

[monk23785]

yea, i found it really weird aswell, it is quite similar to java, I did a java course last year thats why its bugging me that i can't remember how to do it

[humndislocation]

I don't know perl, but what exactly is it that you want to do? Your question isn't really clear.

"The number of an array" doesn't really make sense.

Your explanation after that doesn't really clarify things either.

It sounds like you might be talking about an associative array, or "hash table", rather than an array, and you want to print a list of keys rather than values? I'm assuming that, because it doesn't really make sense to talk about a regular array that way. If you know the length of a normal array, then you know what all the indices are.

Bear in mind I don't know perl, there could be errors in this because I just looked at some examples on the net and tried to change them without really knowing the syntax all that well.

%capitals = ('china' => 'beijing', 'england' => 'london', 'france' => 'paris', 'norway' => 'oslo', 'italy' => 'rome');
 
# process hash elements
foreach $k (keys (%capitals))
{
        print $k, " ";
}

If you change the names of countries to numbers, then I think that's basically what you're asking for.

[pixelsink]

aaaarrgghhhhh, what planet are you guys from!!!!

I'm just jealous, I wish my brain could do that kinda stuff.

[monk23785]

@titrants=(175,149,122,126,150,169);
$min = $arr[0];
$array = 0;
foreach $t (@titrants) {
if ($t < $min) {
$min = $t;

}
print "Minium is $min\n";


I got that so far, but to the print statement i need to add the arraynumber becuase im using the following set of data

Titrant Ohms
0 175
1 148
2 122
3 126
4 150
5 169

The question is write a program to find the minium point on the graph and which point it is

[humndislocation]

Originally Posted by pixels|ink

aaaarrgghhhhh, what planet are you guys from!!!!

I'm just jealous, I wish my brain could do that kinda stuff.

To be fair, I think the exact same thing when I see one of you arty types draw something really awesome, so it all balances out!

[humndislocation]

Ahh right, I see what you want to do now. This isn't really so much of a perl question, as it is a generic programming question (unless there's a specific way to do this in perl).

You need two more variables. One of them holds the current index you are looking at, one of them holds the index of the current min value. You update the current index each time you go through the loop, and you update the current min index each time you change the min.

Sorry, that sounds a bit more complex than it really is. Here's what I'm talking about

@titrants=(175,149,122,126,150,169);
$min = $titrants[0];

$minIndex = 0;
$currentIndex = 0;

foreach $t (@titrants) 
{
  
  if ($t < $min) 
  {
	$min = $t;
        $minIndex = $currentIndex;
  }

  $currentIndex = $currentIndex + 1;

}

Then you just print $minIndex and $min at the end

[monk23785]

looks easy once youve seen it, i ended up just adding in some 'if else' statements because that was th eonly thing i could think of, it did work but it was a bit long winded

[Red_Baron]

You could actually be really fly and only keep a record of the index of the lowest element the just print the that index and the value at that index

@titrants=(175,149,122,126,150,169);
$min = $titrants[0];

$minIndex = 0;
$currentIndex = 0;

foreach $t (@titrants) 
{
  
  if ($t < $min) 
  {
	$minIndex = $currentIndex;
  }

  $currentIndex = $currentIndex + 1;

}

print "Minium is $titrants[$minIndex ] at position $minIndex";

Not entirely sure of the syntax for perl but you should get the gist.

[humndislocation]

Yeah, that's actually a hell of a lot smarter than my solution.

I must say though, Perl has to be up there as one of the ugliest non-joke languages I have ever seen.

Give me Python or Lua any day.

[Red_Baron]

Originally Posted by humndislocation

Yeah, that's actually a hell of a lot smarter than my solution.

I must say though, Perl has to be up there as one of the ugliest non-joke languages I have ever seen.

Give me Python or Lua any day.

I'd agree with you there Perl has dreadful syntax, Python is a much better. Once you get used to needing tabs before it will compile.Code acually becomes neater as a result.

My favourite at the moment (mostly beause I'm working with it most of the time) is PL/SQL, based on ADA if I remember correctly, it makes life very easy with type anchoring and extensions to SQL.