I'm trying to calculate difference of dates based on the current computer date, in ROS. Which function can I use to do that? Or atleast get the current date of computer.
Thanks in advance
You should try Google next time, but here:
ros::Time::now();
ros::Duration difference = ros::Time::now() - previous_time;
http://wiki.ros.org/roscpp/Overview/Time
EDIT:
To get a text string, you have to convert it: https://code.ros.org/trac/ros/ticket/2030
boost::posix_time thistime = from_time_t(difference);
Once you have it converted to boost::posix_time, you can:
std::string to_simple_string(thistime);
Which will spit it out like: "2002-Jan-01 10:00:01.123456789"
You can also see what thistime.date(); gives you, it looks like it might be simpler: http://www.boost.org/doc/libs/1_31_0/libs/date_time/doc/class_date.html
Related
I have a requirement to get current year in the Postman pre-req script.
I'm planning to get the current date, then convert the date to string and apply sub-string to get year value
I would like to know, is this the right way of doing it, or is there any pre-defined function available to do it?
I guess there is no pre-defined function to get year alone may be you can try like below,
const moment = require('moment');
pm.globals.set("timestamp", moment().format("MM/DD/YYYY"));
Then reference {{timestamp}} where ever you need it.
check the link for more details
To get year -
var moment = require('moment');
console.log("timestamp", moment().format("YYYY"));
or even without using moment library -
console.log(new Date());
Another way to get current year :
new Date().getFullYear();
var currentYear=new Date().getFullYear();
postman.setEnvironmentVariable("currentYear" , currentYear);
This worked for me.
I have a dataset that I am trying to manipulate in GraphLab. I want to convert a UNIX Epoch timestamp from the input file (converted to an SFrame) into a human readable format so I can do analysis based on hour of day and day of week.
time_array is the column/feature of the SFrame sf representing the timestamp, I have broken out just the EPOCH time to simplify things. I know how to convert the time of one row, but I want a vector operation. Here is what I have for one row.
time_array = sf['timestamp']
datetime.datetime.fromtimestamp(time_array[0]).strftime('%Y-%m-%d %H')
You can also get parts of the time from the timestamp to create another column, by which to filter (e.g., get the hour):
sf['hour'] = [x.strftime('%H')for x in sf['timestamp']]
So after staring at this for awhile and then posting the question it came to me, hopefully someone else can benefit as well. Use the .apply method with the datetime.datetime() function
sf['date_string'] = sf['timestamp'].apply(lambda x: datetime.datetime.fromtimestamp(x).strftime('%Y-%m-%d %H'))
you can also use the split_datetime API to split the timestamp to multiple columns:
split_datetime('timestamp',limit=['hour','minute'])
I am receiving a datetime in YYYY-MM-DDThh:mm:ss[.S+][Z|+-hh:mm] this format. and i m trying to copy that value using strptime as shown below
struct tm time = {0};
char *pEnd = strptime(datetime, "%Y-%m-%dT%H:%M:%S%Z", &time);
But I can't copy the fraction of seconds as strptime doesn't support it in C++.
So what should i do?
I found a solution using gettimeofday(). but I am already getting date and time in 'datetime' so please help me to find soluntion for it...I can use poco also . but even their we take local time.
You can remove the "S" component from the string before parsing with strptime, then use it however you like later (it won't fit anywhere in a Standard struct tm - there's no sub-second fields). Just datetime.find('.') and go from there, or use a regexp if you prefer - both tedious but not rocket science.
In C++11 you can use the the high precision timing objects in <chrono>, see the answers to this question.
I need to pull a date out of a string. Since not everyone uses the official ISO format when printing their dates, it is impractical to write a date parser for every possible date format that could be used, and I need to handle as many date formats as possible - I don't control the data and can't expect it to come in a specific format.
This seems like a problem that has probably already been solved ages ago, but my Google-fu is too weak to find the solution. :(
Does there already exist a C++ library that, given a string, will return the month, day, year, hour, minute, second, etc that is referenced in that string, if any?
Pseudocode:
string s1 = "There is an expected meteor shower this Thursday,"
"August 15th 2013 at 4:39 AM.";
string s2 = "20130815T04:39:00";
date d1 = magicConverter(s1);
date d2 = magicConverter(s2);
assert(d1 == d2);
You might use the code from here, but you need to configure a mask, that tells the code which time format is used. If you write a class routine, that takes a mask and a string and gets you out the time and is able to print in any format you like, you should be well prepared. You have to look in more detail, if it also supports Daynames and Monthnames. I got it to work in python with a module providing a function that seems pretty much the same.
For more detail:
Please look at the example 2013-08-03 again. Nobody and as follows no computer is able to tell you if this date belongs to August or April, except of having a mask telling JJJJ-MM-DD or JJJJ-DD-MM. Also this library may tell you only standard masked times. So it might lead you to August in this case. But as you said it can be any date declaration, thus it does not need to follow standards, thus it can also mean March. An other possibility is to tell you about the date from the context (e.g. a table with a column of all te same time formats by looking for the increase (which would also fail if you just look at one day per month for just one year).
Another example... if I ask you 2013-05-04... to which month does it belong? You might tell me... April. I would reply "no, to the 4th of May" and vice versa for May and 5th of April. If you tell me how to solve this puzzle with two possible solutions I would understand your downvote... please think before downvoting someone trying to help you.
I'm using Qt to parse an XML file which contains timestamps in UTC. Within the program, of course, I'd like them to change to local time. In the XML file, the timestamps look like this: "2009-07-30T00:32:00Z".
Unfortunately, when using the QDateTime::fromString() method, these timestamps are interpreted as being in the local timezone. The hacky way to solve this is to add or subtract the correct timezone offset from this time to convert it to "true" local time. However, is there any way to make Qt realize that I am importing a UTC timestamp and then automatically convert it to local time?
Do it like this:
QDateTime timestamp = QDateTime::fromString(thestring);
timestamp.setTimeSpec(Qt::UTC); // mark the timestamp as UTC (but don't convert it)
timestamp = timestamp.toLocalTime() // convert to local time
try using the setTime_t function.
Note that full time zone support is not available yet in Qt, but probably will in future versions.
http://bugreports.qt-project.org/browse/QTBUG-10219