[SOLVED] Converting a lat/lon coordinate?

[ERuiz]

Hello all,

If I have a variable that stores a coordinate exactly in this format:

N18 23.5725 W66 23.8565

And I need to change this coordinate into decimal degrees such as this:

18.3928, -66.3976

In the example above, in order to get the .xxxx value, we need to divide xx.xxxx by 60 (ej: 23.5725/60 = .3928). Also, I need to have a comma separating the 2 values.

How can this be accomplished? Keep in mind that the letter W or S, needs to be converted to a - (negative sign)

The name of the variable is $position

Thanks for any help.

Regards,

Efrain Ruiz

[ted_chou12]

which way do you need to convert? if is N18 23.5725 is better to have to variables, one for N18 and the other for 23.5725.

[ERuiz]

What you mean, my friend?

Essentially, I just want the final variable to be in the following format: "xx.xxxx, xx.xxxx" instead of being "Nxx xx.xxxx Wxx xx.xxxx"

Maybe you can separate the values for better manipulation, but once all converting is done, I would like to have the final variable as described above.

[ted_chou12]

<?php
$degrees = explode(" ",$position);
$number = $degrees[1]/60;
if (substr($degrees[0], 0, 1) == N){$answer = $number + substr($degrees[0], 1, 4);}
if (substr($degrees[0], 0, 1) == W){$answer = 0 - 2*($number + substr($degrees[0], 1, 4);}
?>

sorry, the 1 should be 0

[ERuiz]

Do I need to change the {} to ()?

[ted_chou12]

nope, those cannot be brackets...

[ERuiz]

Ok, I will give it a try :-)

[ted_chou12]

hey, Efrain, does it work, i modified it, the $degrees[0] in the if statements should be $degrees[1], you see them?

[ERuiz]

Hi buddy,

I gave this a try and I get the following error:

syntax error, unexpected ';'

The line it says the error is in, points to the second "if" line

[ted_chou12]

opps sorry, i forgot to close the if bracket...
<?php
$degrees = explode(" ",$position);
$number = $degrees[1]/60;
if (substr($degrees[0], 0, 1) == N){$answer = $number + substr($degrees[0], 1, 4);}
if (substr($degrees[0], 0, 1) == W){$answer = 0 - 2*($number + substr($degrees[0], 1, 4));}
?>

[ERuiz]

Cool, now I didn't get the error. But how do I display the final value? What is the variable the result is stored in? Pardon my ignorance...  :-[

[ted_chou12]

the value is stored in $answer... if you tried echo $answer; and nothing comes out, then there is a syntax problem

[ted_chou12]

I think there are some errors with the code, hold on, i will have a look at it

[ERuiz]

I tried the echo command, and nothing was displayed.

[ted_chou12]

here this should work...
<?php
$degrees = explode(" ",$position);
$number = ($degrees[1]/60);
if (substr($degrees[0], 0, 1) == "N"){$answer = $number + substr($degrees[0], 1, 3);}
if (substr($degrees[0], 0, 1) == "W"){$answer = 0 - ($number + substr($degrees[0], 1, 3));}
echo "$answer";
?>

MODIFIED, PLEASE RECHECK AGAIN...

[ted_chou12]

okay, yeah it works, i tested for N18 23.5725  :P took me a while... by the way, how many digits are there for N18 or W66? because my script only works if there are two digits (18 and 66)

[ERuiz]

Ok, it works but partially.

In the current scenario, $Position has this value "N40 38.4541 W73 47.0027"

$answer is giving this result "40.6409016667"

As you can see, it is doing the correct conversion but it's missing the other coordinate. So far so good my friend! ;-) You are almost there!

[ted_chou12]

This is the last post I am making...
[code]
<?php
$position = "W66 23.8565";//here we give a dummy variable to see if it works or not, and all your other inputs should be in this format...
$degrees = explode(" ",$position);
$number = ($degrees[1]/60);
if (substr($degrees[0], 0, 1) == "N"){$answer = $number + substr($degrees[0], 1, 3);}//if is N, we leave the number
if (substr($degrees[0], 0, 1) == "W"){$answer = 0 - ($number + substr($degrees[0], 1, 3));}//if is W, we do 0 minus the answer so we get the negative answer..
echo $answer;//here we echo the answer
?>
[/code]
hope you got through it... and i am really bad coder, kind of speeding my progress as well, so a bit rushed...
this should work no matter two or three digits of N or W...
hope you become a great mathmatician ERuiz  ;)

[ted_chou12]

sorry, i didnt see your last post...
i cant separate "N40 38.4541 W73 47.0027", because there are also spaces bewteen the N40 and 38 as well as W73 and 47, if you have them like this: "N40 38.4541-W73 47.0027", it will be much easier as well as this: "N40-38.4541 W73-47.0027".

[ERuiz]

hmmmm So if there are 2 whitespaces, we can't separate them or trim the values?

[ted_chou12]

not exactly, an expert might find a way out, but i am kind of a starter...

[ERuiz]

Starter? I wish I knew what you know! lol But seriously, I am in debt for all your help, my friend. I will use what you gave me to experiment around. If I come up with something, I will let you know! I think

Thanks a million!

[ted_chou12]

hold on.. let me think logically... the computer goes from left to right... so it recognizes the spaces in order right? hold on a while...

[ted_chou12]

can you give me the answer to the second one please, i want to check...

[ERuiz]

Yup, it checks from left to right. Checkout this page, regarding the explode() function

http://www.phpdig.net/ref/rn58re1163.html

http://us3.php.net/explode