Doubles are giving me problems


Posted on 16th Feb 2014 07:03 pm by admin

Ok so, first of all i made a double = 0.05, but when running the debugger it shows up as 0.04999. I know this has something to do with how doubles store but its causing problems for me. Anyway, in the code I'm trying to get only the right hand side(rhs) of the double variable jdn's decimal point. So in the code example I'm only trying to get .05. But rhs isn't always going to be the same and can have up to 0.00005 <- that fifth one there(can't remember what its called - hundred thousandth?). I have constant numbers right now for the sake of testing this. Now the counter goes through starting at 0.1, to make sure everything after the decimal point is 0. It goes through fine until it gets to 0.0002 - 0.0001 and then rhs = 9.99998e-005.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
#include #include #include using namespace std; int main() { double jdn = 2454115.05; double lhs = floor(jdn); double rhs = jdn - lhs; double counter = 0.1; if( rhs != 0.0 ) while( (rhs != 0.000001) || (counter != 0.00001) ) { if( (rhs - counter) <= 0 ) { counter *= 0.1; //cout << "rhs = " << rhs << endl; } else { rhs -= counter; cout << "rhs = " << rhs << endl; } } cout << "ok" << endl; return 0; }
Results:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
rhs = 0.04 rhs = 0.03 rhs = 0.02 rhs = 0.01 rhs = 0.009 rhs = 0.008 rhs = 0.007 rhs = 0.006 rhs = 0.005 rhs = 0.004 rhs = 0.003 rhs = 0.002 rhs = 0.001 rhs = 0.0009 rhs = 0.0008 rhs = 0.0007 rhs = 0.0006 rhs = 0.0005 rhs = 0.0004 rhs = 0.0003 rhs = 0.0002 rhs = 9.99998e-005

No comments posted yet

Your Answer:

Login to answer
120 Like 6 Dislike
Previous forums Next forums
Other forums

Remore client postprocessing phase getting dump SAPSQL_ARRAY_INSERT_DUPREC
Hello Expects,I have started remore client copy. Data was copied successfully. but while running pos

Displaying image pathname instead of image
Hello

Im trying to upload and then display images from a mysql database - Its only basic and

preg_match logical error
Code: <?php
$s = file_get_contents("page.html");
preg_match('/<div cla

VAT
how should I deal with VAT?

if I have a product that costs £5.00 and VAT @ 17.5% (£0.87

Online Event Ticket Sales
Has anyone wrote a script for online tickets sales?

I have been googling and found lots of th

checkbox update
I am having a brain fart right now and i cant remember how to do this. if anyone could help that wou

Login Script Issues
I am using a script I got from http://phpsense.com/php/php-login-script.html in order to allow peopl

Extracting Long text from message class with parameters
Hi,

I would like to extract the long text from a message class. However, the long text ha

Session
I am having a little trouble with a session. Not sure if it is my browser or what. I know I do not

Javascript or not?
How many people prefer javascript/ajax sites? How many prefer the good old fashion straight php sit

Sign up to write
Sign up now if you have flare of writing..
Login   |   Register
Follow Us
Indyaspeak @ Facebook Indyaspeak @ Twitter Indyaspeak @ Pinterest RSS



 
© indyaspeak.com. All Rights Reserved.
Play Free Quiz and Win Cash