Conversion from d:h:m:s:ms to seconds

Hi folks, I've been given a large data array of timetags that I would like to change to seconds but just don't have the knowledge to be able to do so yet.

I've managed to extract this field's data from a structure, giving me a large 10000x1 cell array of data that looks exactly like this:

%e.g. sample data
%.
%.
'104d:11h:59m:38.934815s'
'104d:11h:59m:38.936032s'
'104d:11h:59m:39.014802s'
'104d:11h:59m:39.016018s'
%.
%.

From this I would like to be able to convert the HOURS, MINUTES, SECONDS and MILLISECONDS all into seconds format to be able to perform calculations with these, negating the days.

Hope someone can help!

Thanks,

C.

Answer 1

[Stephen23]

"negating the days."

I guess you really mean to ignore the days.

format long G
C = {'104d:11h:59m:38.934815s';'104d:11h:59m:38.936032s';'104d:11h:59m:39.014802s';'104d:11h:59m:39.016018s'}

C = 4×1 cell array
    {'104d:11h:59m:38.934815s'}
    {'104d:11h:59m:38.936032s'}
    {'104d:11h:59m:39.014802s'}
    {'104d:11h:59m:39.016018s'}

Method one: SSCANF and matrix multiplication:

M = sscanf([C{:}],'%fd:%fh:%fm:%fs',[4,Inf]).';
V = M * [0;60*60;60;1] % seconds

V = 4×1

1.0e+00 * 43178.934815 43178.936032 43179.014802 43179.016018

Method two: SPLIT, EXTRACTBEFORE, STR2DOUBLE, matrix multplication:

M = str2double(extractBefore(split(C,':'),lettersPattern));
V = M * [0;60*60;60;1] % seconds

V = 4×1

1.0e+00 * 43178.934815 43178.936032 43179.014802 43179.016018

Method three: REPLACE and EXTRACTAFTER and DURATION and SECONDS:

V = seconds(duration(extractAfter(replace(C,lettersPattern,''),':')))

V = 4×1

1.0e+00 * 43178.934815 43178.936032 43179.014802 43179.016018

[Calum]

Thanks so much! This is exremely helpful and gives me lots of options to explore for the future!

Answer 2

[Atsushi Ueno]

format long % to display milli seconds
DateTimeStr = {'104d:11h:59m:38.934815s','104d:11h:59m:38.936032s','104d:11h:59m:39.014802s','104d:11h:59m:39.016018s'};
DateTimeStr = regexprep(DateTimeStr,'\d+d:',''); % negating the days
times = datetime(DateTimeStr,"Format","HH'h:'mm'm:'ss.SSSSSS's'")

times = 1×4 datetime array
   11h:59m:38.934815s   11h:59m:38.936032s   11h:59m:39.014802s   11h:59m:39.016018s

scnds = hour(times).*3600 + minute(times).*60 + second(times);
seconds(scnds) % convert the HOURS, MINUTES, SECONDS and MILLISECONDS all into seconds format

ans = 1×4 duration array
   43178.934815 sec   43178.936032 sec   43179.014802 sec   43179.016018 sec