Calculated duration

[Pyjam]

I would like to add a column: a duration (format h:mm) that is the number of words (#words) divided by 300 in minutes.

Could you help me. Thank you.

[BetterRed]

Originally Posted by Pyjam

I would like to add a column: a duration (format h:mm) that is the number of words (#words) divided by 300 in minutes.

Could you help me. Thank you.

@Pyjam - I have this for video duration, I think you'd need 'hh mm' in the format.



BR

[Pyjam]

Thanks for your help. I have two problems:

1) When a column is based upon another column, I see no place where to input a specific format.

2) I don't know the formula for the the division and the conversion of type.

[chaley]

Originally Posted by Pyjam

I would like to add a column: a duration (format h:mm) that is the number of words (#words) divided by 300 in minutes.

Could you help me. Thank you.

What you want to do pushes the template language to its limits. It isn't designed to do complicated floating point arithmetic such as floor and round, and it doesn't have the notion of "duration".

That said, the following General Program Mode (GPM) template works for me. Since we don't have the duration type we must calculate the parts manually. Since we don't have the "floor" function, the template does the equivalent with string processing to chop off the fractional part from "hours". Fortuitously the number formatter does rounding so we don't need to do that manually when calculating the total minutes as an integer.

program:
	total = format_number(divide(raw_field('#words'), 300), '{0:.0f}');
	hours = re(divide(total, 60), '\..*', '');
	minutes = subtract(total, multiply(hours, 60));
	strcat(hours, ':', format_number(minutes, '{0:02d}'))

For template function documentation see Reference for all built-in template language functions

[BetterRed]

↑ ↑ ↑ ↑ - wot 'e sed

@Pyjam - aaah - you'll need to use the template language, see ==>> The calibre template language Template language is not something in which I have much expertise. I can give some hints though.

I would try doing the arithmetic to get hours and minutes as two discrete integers using then divide function, and then use the format-number and strcat functions to create a string that is the column value.

BR

[Pyjam]

Thanks for your help.

Unfortunately, the columns show the formulae, not the values!

[chaley]

Originally Posted by Pyjam

Thanks for your help.

Unfortunately, the columns show the formulae, not the values!

Then you have not entered the template correctly.

The easiest way to edit composite column (column built from other columns) templates is to edit them on the main book list. Click on any cell in the composite column, press F2 (or whatever Edit is on your OS), and paste the template into the resulting editor.

[Pyjam]

Thanks for your patience. I'd not understood: I'd created separate columns for total, hours, minutes, and final result.

It works very well now. Thank you.