question from perl noob

[boblehue]

Hi

I'm tryng to learn a little perl and have a problems with decimal's.

This asignment is to rewrite this code to not print more the two decimals
with the use of INT operator, multiplication, and division.

print "Monthly deposit amount? ";
$pmt=<STDIN>;
chomp $pmt;

print "Annual Interest rate? (ex. 7% is .07) ";
$interest=<STDIN>;
chomp $interest;

print "Number of months to deposit? ";
$mons=<STDIN>;
chomp $mons;

# Formula requires a monthly interest
$interest/=12;

$total=$pmt * ( ( (1 + $interest) ** $mons ) -1 )/ $interest;

print "After $mons months, at $interest monthly you\n";
print "Will have $total,\n";


Regards
Boblehue

 

[boblehue]

Hi and tnx Garry!

I tryed your code but it did not give me the result i wanted.

With your code : 29498.282425,

With origninal code : 29498.2824251624

Result i'm looking for : 29498.28

I get closer with your code but not quite!

And i'm suposed to use the INT operator, multiplication, and division.

Regards

Boblehue

 

[Chris]

Hi

I'm tryng to learn a little perl and have a problems with decimal's.

This asignment is to rewrite this code to not print more the two decimals
with the use of INT operator, multiplication, and division.

<snip>

The trick is to multiply everything up by 100 so that you're working in
pence, cents, or whatever currency you're dealing with. Then do your
monthly interest multiplication forced to INT and then divide you're
final answer by 100 to get back you're 2 dec. points.

Chris.

 

[Chris]

Garry Short wrote:

$total= sprintf "%2f", ($pmt * ( ( (1 + $interest) ** $mons ) -1 )/
$interest);

<snip>

That should be:

$total= sprintf "%.2f", ($pmt * ( ( (1 + $interest) ** $mons ) -1
)/$interest); ^

Your code tries to round the float to two sig. figs not two dec. places.
The dot will remedy that.

 

[joeri]

Hi and tnx Garry!

I tryed your code but it did not give me the result i wanted.

With your code : 29498.282425,

With origninal code : 29498.2824251624

Result i'm looking for : 29498.28

I get closer with your code but not quite!

And i'm suposed to use the INT operator, multiplication, and division.

Regards

Boblehue

You're right, it should be" %0.2f"

Greets,

J

 

[boblehue]

Or u can use the grey ones and do some math:

$total=$pmt * ( ( ( 1 + $interest) ** $mons ) -1 )/ $interest;
$total=$total * 100;
$total=int($total);
$total=$total/100;

print "After $mons months, at $interest monthly you\n";
print "Will have $total.\n";

I found the solution on my one
One step closer to understand perl...

Regards
Kenneth

 

[Chris]

<snip>

The trick is to multiply everything up by 100 so that you're working in
pence, cents, or whatever currency you're dealing with. Then do your
monthly interest multiplication forced to INT and then divide you're
final answer by 100 to get back you're 2 dec. points.

Chris.

Please excuse the piss-poor grammar. The last two "you're"s should be
"your".

 

[Tintin]

[snipped repeated question in alt.perl]

Please read http://www.cs.tut.fi/~jkorpela/usenet/xpost.html

 

[Chris Mattern]

Hi and tnx Garry!

I tryed your code but it did not give me the result i wanted.

With your code : 29498.282425,

With origninal code : 29498.2824251624

Result i'm looking for : 29498.28

I get closer with your code but not quite!

And i'm suposed to use the INT operator, multiplication, and division.

And just why are you limited to those functions?

I smell homework.

Chris Mattern