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hi
i am using int32 variable name 'count' and 'totalcount' to get the total number of students for boys and girls. the total number is found fine,
i want to calculate the %age also

count = ((count * 100) / totalcount);

it generates the resultant number but i want the round figure ie 29.8 is displayed as 29, it is making problem in completing the total 100 %
Posted 6-Sep-11 20:55pm
Updated 28-Dec-16 22:54pm
Comments
koolprasad2003 7-Sep-11 3:11am
   
Do u want Round of value ? use "System.Math.Round(//val));"
yesotaso 7-Sep-11 17:37pm
   
Common C Programming Errors or you can say "C alike"...
double fifty = (1/2) * 100;
This code sets fifty to 0 not 50! Why? Because of integer division.
If you want something nailed use hammer, if you want something sliced use a knife...
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Solution 4

To have the totals add up to 100, your in best bet is to keep the calculations decimal not int and format the decimals when showing in your UI to show integers only (format string = "0").
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Comments
lukeer 7-Sep-11 6:17am
   
+5 for using decimal
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Solution 6

A general solution to ensure that a rounded collection of numbers still adds up to the same as it did before is quite difficult. However, I think you are just doing two numbers, so one is 100% minus the other:
int boys_pc = (int)(0.5f + ((100f * boys_count) / total_count));
int girls_pc = 100 - boys_pc;


Cast to float to avoid integer division giving you a zero, and add 0.5 for integer rounding. Use 0.5f not 0.5 to keep it from expanding to double (which is overkill for something which will be rounded to int anyway).

Edit: If you have to multiply anyway, just multiply by a float constant (e.g. 100f not 100) to avoid integer division.
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v3
Comments
lukeer 7-Sep-11 6:15am
   
I think there is an error in your calculation.
Think of 80 boys out of 100 students.
That would be a rate of 0.8 (innermost parentheses). Adding 0.5F would exceed 100%. Hence, girls percentage would go negative.
BobJanova 7-Sep-11 13:12pm
   
Uh yeah I forgot to multiply by 100 first. (The OP wants 0-100, not 0-1.) Thanks.
Member 12867845 29-Dec-16 4:55am
   
dhdhdhdh
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Solution 2

Use
System.Math.Round()
method.
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Solution 3

Use Math.Round(56.8) will be 57
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Solution 7

You can use ToString to format how you want the display.
So if you have

double percent;
...
percent = 29.8;
 
...
 
public string PercentDisplay
{
    get{return percent.ToString("00")} //Will always show 2 digits and no decimal
}



In comparison if you always wanted 2 decimal places (even if they are 0's) you can code like this percent.ToString("00.00")
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v3
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Solution 1

percentage should be calculate by below formula

count = ((count / totalcount)*100);
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Comments
Db issues 7-Sep-11 3:08am
   
the result is 0 in that case i tried before,
now i have declared double percent = ((count * 100) / totalcount);
it displays same result but how to round the figure and get the floor/ ceiling function
Anuja Pawar Indore 7-Sep-11 3:18am
   
This will give ans as zero.
if (112/200)*100 will result zero
GParkings 7-Sep-11 4:11am
   
(count/totalcount)*100 is mathematically synonymous with (count * 100) / totalcount
pooja 08 7-Sep-11 5:01am
   
your problem is resolved or not?
Db issues 7-Sep-11 5:08am
   
yes logically there is no difference but i found answer zero, no my problem is still there
pooja 08 7-Sep-11 6:16am
   
try to declare int as int32 i am not sure about it but check?
pooja 08 7-Sep-11 6:32am
   
while showing at ui just convert your count value to TOstring(); it will resolve your problem
W∴ Balboos 29-Dec-16 9:36am
   
LOGICALLY THERE IS A HUGE DIFFERENCE !

The division before multiplying by 100 will (for example) always yield zero if count is less than total count. Multiplying by 100 at that point is a waste of time.

You multiply first, then divide, so that the value will not always be zero.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

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