Help with 3 homework assignments

wilmer007

Hi all i need some help in solving 3 homework assignments that are due on friday.

1) Create a link with functions

2) Create a form functions

3) Create an array for the average age of 10 people = for this we were given a syntax with the persons first name, last name and age. the profesor said we needed to investigate how to divide this so that we can get the average age for all 10 people.

now the problem is that due to a foot injury i was unable to attend class for about 2 to 3 weeks so i'm a little behind in class and still learning php after loving C, Visual Basic and C++ where i had already learned about arrays, and funciones and i already had an understanding of links due to my previous experience with HTML in fórums.

for the first problem i found this: http://board.phpbuilder.com/showthread.php?10324957-Using-hyperlink-to-call-php-function
i'm guessing this is what i need to do the first problem correct?

but for the second problem the page that was redirected from this fórum was not loading so i don't have anything to go by.

for the third problem what do i need to do to divide the syntax in order to find the average age. it sounds like i need to take the array and have it sum up the age of the 10 people and then have it display the average age which is (total age divided by 10).

sneakyimp

Unfortunately, missing class is going to cause you problems. Those 3 points you have look pretty vague to me and going to class would give you a lot more context to understand that "Create a link with functions" really means. There's no way we can answer here whether that's what you need for the first problem.

The second problem is also vague -- as is your explanation of "page not loading." You could start by creating an HTML form.

Arrays in C and C++ are a pain in the ass. PHP makes them super easy. If you want to sort an array that has more than just numbers in it, you'll probably need to create an array of associative arrays and use [man]usort[/man] to sort it.

wilmer007

i asked the profesor yesterday and those were his exact words of what we needed to do so when he said create a link with functions and create a form with functions thats what he wants. he said we can choose what kind of topic we want to put so like if i'm want to make a link that has a function for a calculator then i can do that which is more or less the topic i had in mind. as for create a form with functions well that is pretty standard since i can just make a function that stores multuple people that is signing up for a website such as a forum, facebook, etc..

i don't have class again until friday so i can't exactly ask the professor again when i can't even see him and he has already explained the 3 assignments.

sneakyimp

Not sure what to tell you then. You need to get clearer on the assignment and ask a more specific question. Maybe you're not getting your money's worth for your tuition.

wilmer007

well i was able to complete the homework just in time for class. thanks to a classmate who linked me to this:

http://php.net/manual/en/function.explode.php

i was able to use that to make 10 explodes (one for each person) then make a variable that stores age in other words:

$total = $total + $age;

i put that into each explode so that it takes the previous total age and then adds the new age to the total age until it gets to the 10th explode. once it finished it was just a matter of making a new variable which divides the total age by 10 to get the average age so something like this:

$average = $total /10;

i do have a question though. how would i use this explode for lots of people?
like what if the profesor had told us it was 1000 people. how would i fit this into a loop?

sneakyimp

[man]explode[/man] is used to take a string and break it up into an array by splitting it up into smaller strings based on some delimiter character like a comma or a tab or something.

How you create an array for 1000 people depends on two things:
1) the input format (which you have neglected to specify to us). I'm guessing it's some kind of string that uses delimiters
2) what kind of array you want for output. It sounds like you are happy enough creating numerically-indexed arrays. Personally, I would prefer associative arrays for each person.

$one_person = array(
  "first_name" => "Marty",
  "last_name" => "McFly",
  "age" => 17
);

wilmer007

sneakyimp;11049131 wrote:
[man]explode[/man] is used to take a string and break it up into an array by splitting it up into smaller strings based on some delimiter character like a comma or a tab or something.

How you create an array for 1000 people depends on two things:
1) the input format (which you have neglected to specify to us). I'm guessing it's some kind of string that uses delimiters
2) what kind of array you want for output. It sounds like you are happy enough creating numerically-indexed arrays. Personally, I would prefer associative arrays for each person.
$one_person = array(
  "first_name" => "Marty",
  "last_name" => "McFly",
  "age" => 17
);

umm i still don't understand how you specify the array for 1000 ppl. sounds like your saying i wouldn't needed to use a for loop but what would the syntax look like for 1000 people. that only shows one person.

sneakyimp

Did you even read my post?

sneakyimp wrote:
How you create an array for 1000 people depends on two things:
1) the input format (which you have neglected to specify to us). I'm guessing it's some kind of string that uses delimiters
2) what kind of array you want for output. It sounds like you are happy enough creating numerically-indexed arrays. Personally, I would prefer associative arrays for each person.

wilmer007

sneakyimp;11049143 wrote:
Did you even read my post?

i read it but understanding it without an example is a different story.

dalecosp

back2.txt:

McFly, Marty, 17
Brown, Emmett, 63
Tannen, Biff, 48
Parker, Jennifer, 17

<?php

$raw_data = file("/path/to/back2.txt"); //yields an array, $raw_data; each element is a line from the file.

$out_data = array();  //this will contain the output array
$n = 0;  // a counter used in creating the multi-dimensional array $out_data initialized above....

foreach ( $raw_data as $line ) {

   $line_data = explode( ",", $line );
   $out_data[$n]['first_name'] = trim( $line_data[1] ); // because the txt file has lastname 1st ...
   $out_data[$n]['last_name'] = trim( $line_data[0] ); // we assign the elements in this order to match
   $out_data[$n]['age'] = trim( $line_data[2] );          // sneakyimp's example
   $n++;
}

print_r( $out_data );

Result:

Array
(
    [0] => Array
        (
            [first_name] => Marty
            [last_name] => McFly
            [age] =>  17

    )

[1] => Array
    (
        [first_name] => Emmett
        [last_name] => Brown
        [age] =>  63

    )

[2] => Array
    (
        [first_name] => Biff
        [last_name] => Tannen
        [age] =>  48

    )

[3] => Array
    (
        [first_name] => Jennifer
        [last_name] => Parker
        [age] =>  17

    )

)

Derokorian

I dunno why, but I felt like taking your input format and going all gun-ho on it... here's what I came up with:

$output_data = array_map(function($el) {
    return array_combine(
        ['last_name','first_name','age'],
        array_map('trim', explode(',', $el))
    );
}, file("back2.txt"));

print_r( $out_data );

dalecosp

Derokorian;11049163 wrote:
I dunno why, but I felt like taking your input format and going all gun-ho on it... here's what I came up with:
$output_data = array_map(function($el) {
    return array_combine(
        ['last_name','first_name','age'],
        array_map('trim', explode(',', $el))
    );
}, file("back2.txt"));

print_r( $out_data );

Well, it's possibly either like standing at the urinal in 4th grade :rolleyes: ... or maybe it's just that you enjoy a challenge. Nicely done 😉 🙂

sneakyimp

I don't recall the OP ever specifying what the input format was.

dalecosp

Well, no; it was mentioned, but not very specifically, so we made up one and ran with it, the point being to educate rather than actually do ALL the homework for him/her....

Derokorian

dalecosp;11049171 wrote:
Well, it's possibly either like standing at the urinal in 4th grade :rolleyes: ... or maybe it's just that you enjoy a challenge. Nicely done 😉 🙂

[ATTACH=CONFIG]5223[/ATTACH]

I have no projects outside of work at the moment, feeling a little under-challenged 😛

743581.jpg

wilmer007

well i had already turned in the homework anyways. i was just curious how you could do this for 1000 people since you aren't going to manually enter 1000 different identities.

problem is i still dont understand in those examples how you tell php to do it for 1000. my guess is that i would need to set up a form so that the user inputs his info. i don't know i enjoyed and understood C and C++ but PHP seems harder for me to understand and i'm not enjoying it either. 🙁

sneakyimp

wilmer007;11049191 wrote:
well i had already turned in the homework anyways. i was just curious how you could do this for 1000 people since you aren't going to manually enter 1000 different identities.

The names have to come from somewhere. My guess is that your homework assignment had a specific input format that you were supposed to work with and you never managed to show us what that format was.

As for 'how to do 1000', [man]explode[/man] doesn't really care how many records are in a string -- unless there are so many that your computer is running out of memory. All 'explode' does is take some string and split it up using some delimiter and then it takes all the parts that result and puts them all into an [man]array[/man].

You could also use some kind of function like [man]fgetcsv[/man] <--the documentation has examples of how to use it. The basic idea is that you use [man]fopen[/man] to open some kind of file and then you create a loop to keep reading in data until it gets to the end of the file.

wilmer007;11049191 wrote:
problem is i still dont understand in those examples how you tell php to do it for 1000. my guess is that i would need to set up a form so that the user inputs his info

That certainly sounds like a good way to collect 1000 names -- if you know 1000 people you can get to come enter the data into the form. It's my guess that this was not necessarily part of the homework assignment.

wilmer007

sneakyimp;11049193 wrote:
The names have to come from somewhere. My guess is that your homework assignment had a specific input format that you were supposed to work with and you never managed to show us what that format was.

As for 'how to do 1000', [man]explode[/man] doesn't really care how many records are in a string -- unless there are so many that your computer is running out of memory. All 'explode' does is take some string and split it up using some delimiter and then it takes all the parts that result and puts them all into an [man]array[/man].

You could also use some kind of function like [man]fgetcsv[/man] <--the documentation has examples of how to use it. The basic idea is that you use [man]fopen[/man] to open some kind of file and then you create a loop to keep reading in data until it gets to the end of the file.

That certainly sounds like a good way to collect 1000 names -- if you know 1000 people you can get to come enter the data into the form. It's my guess that this was not necessarily part of the homework assignment.

no it wasn't part of the assignment i was just curious. the assignment was for 10 people. but our professors like to use Universities as examples. In programming 1 and 3 it was the same professor and he would tell us it was 500 students and when we did C he would tell us to do the loop for 3 students and then all we had to do was the change the 3 to 500 to match the assignment since we weren't gonna sit there and manually enter 500 fake students.

dalecosp

sneakyimp;11049193 wrote:
That certainly sounds like a good way to collect 1000 names -- if you know 1000 people you can get to come enter the data into the form. It's my guess that this was not necessarily part of the homework assignment.

Well, I guess if you want names you can just try the US OPM :rolleyes: