Rounding to nearest integer in Custom Column - Hijri Year

[oelgamal]

Hello,

I have a column for the year the book was written in the Gregorian calendar, and also another column for the year in the Hijri Lunar calendar

I called the first column gyear, and the second column hyear. they are related by the simple formula hyear = (33/32)*(gyear - 622)

So made a column built from other columns, and called it hyear and gave it the following template,

{#hyear:'multiply(divide(33,32),subtract(field('#g year'),622))'}

and it works fine, except the result is a float with 4 decimal places, and I want to round it to the nearest integer. I tried

{#hyear:'format_number(multiply(divide(33,32),subt ract(field('#gyear'),622)),'{0:d}')'}

to do this but it does not work, it simply shows blank.

Please let me know how to do this, I am sure it is a very simple feature I simply overlooked.

P.S. I posted this under the wrong section previously.

Thanks

[chaley]

The problem is that you are using the characters { and } in the template in template program mode. Those characters are special. In single function mode or in template program mode, anything between { and } is evaluated before the template itself is evaluated. I realize that this fact isn't made clear by the documentation. It is mentioned in the docs for the eval function, but that might not help much. I will look at fixing this lack. But regardless ...

If you want to use the { and } characters in a template, which you must do if you are using format_number, then you must use general program mode. A GPM template that computes what you specify is

program: format_number(multiply(divide(33,32),subtract(field('#gyear'),622)), '{0:.0f}')

However, note that there is no guarantee that the result is rounded. If you want to be certain to round, then you should add 0.5 to the result before you format it.

If this template will be used in a composite custom column then I suggest you precompute 33/32 to whatever precision you want and use that number. There is no point in recomputing that number for every book. which is what the template would do if the divide is left in.

[oelgamal]

Thank you very much, it works now! I would not have found it on my own.

I think may be a small section in the documentation section with sample uses would be nice.

peace