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How to get the sum of multiple time fields in Crystal Reports

The information in the article refers to:
Seagate Crystal Reports 8

Applies to:

Reported version and higher
summing time fields
converting seconds to hours, minutes, seconds

Synopsis

A report contains a time field that displays in hh:mm:ss format.

How do you create a formula in Crystal Reports (CR) to get the sum of more than one time field
and to display the total of those time fields in the same format (hh:mm:ss).

For example:

1:45:01 + 1:45:01 should display 03:30:02 and not 2:90:02

Solution

In order to get the sum of more than one time field
and to display the total of the time fields in the
same format (hh:mm:ss), you must complete the
following steps:

1. Convert all the time fields to a common time
unit such as seconds

2. Calculate the total time in seconds

3. Convert the seconds back to hh:mm:ss format.

Convert time fields to seconds
-----------------------------

Convert the time fields to seconds so that a
common time unit is used to sum up all three
different time units.

If your field is a datetime field, complete the
following steps:

1. Create a new formula and call it
@ConvertTimeToSeconds

2. To convert the datetime field to seconds,
create a formula similar to the following:

local numbervar hours;
local numbervar minutes;
local numbervar seconds;

// Convert the hours to seconds by multiplying by
// 3600
hours := hour({@time}) * 3600;

// Convert the minutes to seconds by multiplying by
// 60
minutes := minute({@time}) * 60;
seconds := second({@time});

//add up all the seconds
hours + minutes + seconds;

To convert the string field, with the format of
hh:mm:ss to seconds create a formula similar to the
following:

1. Create a new formula and call it
@ConvertTimeStringToSeconds

2. Create a formula similar to the following to
convert the string field to seconds:

local numbervar hours;
local numbervar minutes;
local numbervar seconds;

// Parse out the hours portion of the string and
// multiply by 3600 to convert to seconds
hours := tonumber({timestringfield}[1 to 2])* 3600;

// Parse out the minutes portion of the string and
// multiply by 60 to convert to seconds
minutes := tonumber({timestringfield}[4 to 5]) * 60;

// Parse out the seconds
seconds := tonumber({timestringfield}[7 to 8]);

// Add up all the seconds
hours + minutes + seconds;

Calculate the total time in seconds
---------------------------------

Create a summary formula that will sum the
@ConvertTimeToSeconds or @ConvertTimeStringToSeconds

1. Create a new formula and call it @TotalSeconds

2. To sum up either formula, create a formula
similar to the following:

sum(@ConvertTimeToSeconds, Group)

- OR -

sum(@ConvertTimeStringToSeconds, Group)

Convert the seconds back to hh:mm:ss format
---------------------------------------------

Create a formula that converts the @TotalSeconds
results back to hh:mm:ss format.

1. Create a new formula and call it
@ConvertTotalSeconds

2. To convert the results from @TotalSeconds back
to hh:mm:ss format, create a formula similar to the
following:

local numbervar RemainingSeconds;
local numbervar Hours ;
local numbervar Minutes;
local numbervar Seconds;

//divide the @TotalSeconds by 3600 to calculate
// hours. Use truncate to remove the decimal portion.
Hours := truncate({@TotalSeconds} / 3600);

// Subtract the hours portion to get RemainingSeconds
RemainingSeconds := {@TotalSeconds} - (Hours *
3600);

// Divide RemainingSeconds by 60 to get minutes.
// Use truncate to remove the decimal portion.
Minutes := truncate(RemainingSeconds/60);

// Subtract the Hours and Minutes and what is left
// over is seconds.
Seconds := {@Totalseconds} - (Hours * 3600) -
(Minutes * 60);

// Format the hours, minutes, and seconds to hh:mm:ss
totext(Hours,"00") + ":" + totext(Minutes,"00") +
":" + totext(Seconds,"00")