Problems with array and for.

Programming Questions

mrenglet

in Programming Questions • 6 months ago

Hi everyone,

I'm quiet new in the magic world of Processing and I got a little problem, and i can't fix it ...

First, i'm gonna explain my project. I want to take the number of times of each letter appair in a tex (A,B,C,D,...) make something with it (I don't know yet). But i can't get the number of each letter by using a for (because i don't know very much about array and for...).

So here is my code :

String [] texte= {

"A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"

};

void setup() {

size(800, 800);

textAlign(LEFT);

String [] textecomplet;

textecomplet=loadStrings("text.txt");

String texteunique;

texteunique=join(textecomplet, "");

texteunique=texteunique.toUpperCase();

String toutelettre=join(textecomplet, "");

int total =toutelettre.length();

int i = 0;

int k=0;

for (i=0; i<26;i=i+1) {

String[] a=new String[26];

a [i] = texteunique.replace(texte[i], "");

int[] a2 = new int[26];

a2[i]=a[i].length();

int[] a3 = new int[26];

a3[i] = total-a2[i];

}

PS : Sorry for the english, isn't my mother language.

Thanks.

Replies(4)

pauline303

Re: Problems with array and for.

6 months ago

little point of start:

String string;

string= "aaaaa";
int count = 0;
for(int i =0; i < string.length(); i++)
      if(string.charAt(i) == 'a')
          count++;
          println(count);

PhiLho

Re: Problems with array and for.

6 months ago

Mmm, indeed...
First problem: you declare the arrays inside the loop. This means that these arrays are lost at the end of each iteration, and recreated at the start of the next one...
You have to declare them before the loop.
Second problem: well, your algorithm is a bit... strange.
You can get a character at a given position with textunique.charAt(i) where i is between 0 and textunique.length() - 1 (inclusive).
A character in Java is actually a number: you can do arithmetic operations on them.
char c = textunique.charAt(i);
int pos = c - 'A'; // 0 for A, 1 for B, etc.
Beware of characters not in the alphabet, check the result is between 0 and 25, and reject values outside it.
With pos, you can increment the count of these characters:
count[pos]++; // Add one to the variable

I hope I pushed you in the right direction...
(Et un salut de Paris...)

mrenglet

Re: Problems with array and for.

6 months ago

thanks to both of you for the quick and good answer!

Thanks Pauline for the help but it's not what i'm looking for, because i want a loop of all letter not juste one ... (sorry but i really really want to do it in a loop for every letter).

Next, PhiLho, tanks also for the answer !

I understand the first problem, so i need to put my arrrays outside of the loop, it's quiet logical.

Yep my algorithm must look very strange, I never learn Java or any coding thing, I just start like 6 months ago to use Processing.

So about

char c = textunique.charAt(i);

int pos = c - 'A'; // 0 for A, 1 for B, ect.

So the int pos give me a 0 for A, a 1 for B, ect ... but what can i do with those ?

The really problem i get was to extract the value of each letter and get them print on the screen ... !

Because I already made to find the value of each letter ...

I'm gonna try it tomorrow or later during the night ;) !

Thanks again to both of you !

(Et un salut de Bruxelles!)

GoToLoop

Re: Problems with array and for.

6 months ago

I would say that this post of today is very similar to what you want to accomplish too:
http://forum.processing.org/topic/stringarrayindexoutofbounds

The only catch is he just wanted total # of vowels + y; and you, in turn, want whole alphabet!
What an almost coincidence!