help

[lichy]

i need help.

for example, my input is AAXXXAAXXXAAXX

so i want to count the number of times the AA actually appear in total. that will be 3 times. how to write a program like this?

[KevinADC]

double-post, see below.........

[KevinADC]

Really mate, this is too simple, next time post some code you have tried.

two ways:

$input = 'AAXXXAAXXXAAXXAXA';
$count = $input =~ s/(AA)/$1/g;
print $count;

$input = 'AAXXXAAXXXAAXXAXXA';
$count = () = $input =~ /AA/g;
print $count;

but what is if the input has three or more 'A's in a row? For example:

AAXXXAAXXXAAXXAXAAAXXAAAAAXXAA

[lichy]

as for that, i still have to verify with my teacher in school. to see what he gonna say about that.

btw thanks for helping.

input : AAXXXXAAXXXACXXXACXXX

i would like to count the times AA and AC occurred separately.

i try using your method. but the output is not what i want.
and i try using "if" statement. it's still the same output which is not what i expected.

this is the code for "if" statement.

if($seq =~ AA)
{
$countAA = $seq =~ s/(AA)/$1/g;

print "\nNumbers of AA pairs occurred: $countAA";
}

if($seq =~ AC)
{
$countAC = $seq =~ s/(AC)/$1/g;

print "\nNumbers of AC pairs occurred: $countAC";
}

[KevinADC]

the "if" conditions are not necessary:

$seq = 'AAXXXXAAXXXACXXXACXXX';
$countAA = $seq =~ s/(AA)/$1/g;
print "\nNumbers of AA pairs occurred: $countAA";
$countAC = $seq =~ s/(AC)/$1/g;
print "\nNumbers of AC pairs occurred: $countAC";

both substrings (AA and AC) are counted twice, so the code works as expected.

From now on if you post questions I will not reply unless i see the code you have been writing and trying. That is my personal policy for helping students.

[lichy]

ok noted.

btw instead of putting

$count = $seq =~ s/(AA)/$1/g;
print $count;

can i put

$count = $seq =~ s/($codon)/$1/g;
print $count;

as for the $codon, it's a input for the user to type in.

[KevinADC]

try it and see what happens. This is the kind of thing that is easy to run a test on and see what the results are.