Mathematical operators

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Views: 468 | Replies: 4 | Solved

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Join Date: Jan 2008

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eddy556

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Mathematical operators

Feb 5th, 2008

I'm having problems performing math in JSP. I have a line:

double percentage = (useful / nonuseful) * 100;

which is giving me an error, how do I fix this?

Thanks

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Join Date: Jan 2008

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Reputation: electron33 is an unknown quantity at this point

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electron33 electron33 is offline

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Re: Mathematical operators

Feb 5th, 2008

<%

        double useful = 12;

        double nonuseful = 24;

        double percentage = ( useful / nonuseful ) * 100;

    %>

    <%= percentage %>

In this example it will be 50.0 in the JSP page.

Last edited by electron33 : Feb 5th, 2008 at 3:17 pm.

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Join Date: Jan 2008

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eddy556

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Re: Mathematical operators

Feb 5th, 2008

Okay now I'm getting errors about doubles and integers the values in the database are stored as doubles

Type mismatch: cannot convert from double to int

136: double useful = columns.getDouble("Customer_Useful");
137: double nonuseful = columns.getDouble("Customer_NotUseful");
138: votes = useful + nonuseful;
139: double percentage = (useful / nonuseful) * 100;