The 'Subdivide time string' dialog


To split the time string into subgroups based on times of measurements select 'Subdivide time string' in the 'Special' menu. Period04 offers two alternative ways of dividing a time string into substrings. The dialog box prompts the user th choose the desired type of subdivision:

Subdivide by gaps The programm will search for time gaps between consecutive points that are larger than a user-defined value. The data set is then subdivided by these gaps.
Subdivide by fixed intervals If you want to divide the time string into substrings using a fixed time interval then select this option.
According to your selection one of the following dialogs will show up. Below the dialogs an appropriate time string plot shows the difference between the two kinds of subdivisions applied to one and the same data set:
Subdivide by gaps: Subdivide by fixed intervals:

An example for 'Subdivide by gaps':

An example for 'Subdivide by fixed intervals':
For a subdivision the following informations are needed:
Size of the gap Defines the minimum gap size (using the same time unit as your time string). If two consecutive points are separated more than the given value then a subdivision will be made.
Start time Only the data points after this time value will be subdivided. Defaults to the lowest time value of the time string.
Time interval Defines the length of the interval that is being used for the subdivision.
Choose the attribute you want to subdivide Defines the attribute (column) in which the subdivision should take place.
Label prefix The final labels of the substrings are constructed in the following way:
[prefix] + [average time of the substring]
Here you can define this prefix.
Use running counter If this option is selected the program constructs the final label of the substrings in the following way:
[prefix] + [a running counter]
    
Decimal places to use from time The number of digits that will be used for the labels of the substrings.

The inverse operation is "Combine substrings".