matlab timestamp转换

问题 如何将matlab时间戳进行加减

matlab的sac文件时间读取后，需要加上八小时才是本地时间。

用rdsac.m读取后的时间t已经是matlab时间戳的样式，如下

t(1:3)

ans =

737005.94868136
737005.948692934
737005.948704508

:

T是一列生成的时间序列，

t0=datenum(2017,11,06,00,00,00);
dt=1/(24*60*60);
tf=datenum(2017,11,09,23,59,59);
T=t0:dt:tf; T=T';

T(1:3)

ans =

737005
737005.000011574
737005.000023148

解决

usecs = double(T(2)) - double(T(1));%看时间间隔

secsDiff = usecs / 1e6;
tt=t+secsDiff*86400*8; %加上8小时变为本地时间 86400*8*(T(2)-T(1))

 

usecs = double(t(2)) - double(t(1));
% secsDiff = usecs / 1e6;
secsDiff = usecs;
tt=t+secsDiff*3600*8;%加上8小时变为本地时间 3600*8*(T(3)-T(2))

运行结果================

datestr(tt(1:5))

ans =

5×20 char array

'06-Nov-2017 22:46:06'
'06-Nov-2017 22:46:07'
'06-Nov-2017 22:46:08'
'06-Nov-2017 22:46:09'
'06-Nov-2017 22:46:10'

datestr(T(81967:81967+5))

ans =

6×20 char array

'06-Nov-2017 22:46:06'
'06-Nov-2017 22:46:07'
'06-Nov-2017 22:46:08'
'06-Nov-2017 22:46:09'
'06-Nov-2017 22:46:10'

参考

https://stackoverflow.com/questions/10103670/matlab-converting-timestamps-to-readable-format-given-the-reference-date-time