time

问题 The default time.Duration String method formats the duration with adding 0s for minutes and 0m0s for hours. Is there function that I can use that will produce 5m instead 5m0s and 2h instead 2h0m0s ... or I have to implement my own? 回答1: Foreword: I released this utility in github.com/icza/gox, see timex.ShortDuration(). Not in the standard library, but it's really easy to create one: func shortDur(d time.Duration) string { s := d.String() if strings.HasSuffix(s, "m0s") { s = s[:len(s)-2] } if

问题 I recently saw this benchmark: http://jsperf.com/remove-element-splice-vs-move-and-pop I noticed that Array.splice() is several orders of magnitude slower than a for loop iterating through the elements. This lead me to wonder why Array.splice() is so slow. Therefore, I came here to ask you: Why is Array.splice() so slow? 回答1: There is a fallacy in that benchmark: .splice preserves the order of the elements in the array, and therefore needs to move half of the elements until the hole created

问题 I don't need this time associated with any date. In fact, I don't want it associated with a specific date. It's more so associated with a generic day of the week. Monday, Saturday, etc. For example, your local coffee shop sets their hours for Monday based on the fact that it is a Monday. Not based on it being May 22, 2017 or May 29, 2017, etc. I could do something like... "Local Coffee Shoppe": { "availability": { "monday": { "start": { "hour": 7, "minute": 30 }, "end": { "hour": 21, "minute"

问题 I'm struggling to understand how "AT TIME ZONE 'localtime'" exactly work? By playing with it, I found out that it acts exactly as "AT TIME ZONE 'UTC'" ... But why? Is "localtime" a synonym of "UTC" in postgres? Or it comes from some setting (environment? connection timezone? although checked both, seems they are not related)... There's "localtime" function but I think it is not involved here. Sample SQLs: # date Thu Dec 8 12:00:05 AEDT 2016 # SELECT LOCALTIMESTAMP; ---------------------------

问题 I have noticed that loading a CSV file using CSV.read is quite slow. For reference, I am attaching one example of time benchmark: using CSV, DataFrames file = download("https://github.com/foursquare/twofishes") @time CSV.read(file, DataFrame) Output: 9.450861 seconds (22.77 M allocations: 960.541 MiB, 5.48% gc time) 297 rows × 2 columns This is a random dataset, and a python alternate of such operation compiles in fraction of time compared to Julia. Since, julia is faster than python why is

问题 I have noticed that loading a CSV file using CSV.read is quite slow. For reference, I am attaching one example of time benchmark: using CSV, DataFrames file = download("https://github.com/foursquare/twofishes") @time CSV.read(file, DataFrame) Output: 9.450861 seconds (22.77 M allocations: 960.541 MiB, 5.48% gc time) 297 rows × 2 columns This is a random dataset, and a python alternate of such operation compiles in fraction of time compared to Julia. Since, julia is faster than python why is

问题 This may be a dumb question, I'm 99% sure it does, but I need to be sure... does JS use the local computer's time? 回答1: Yes it does use the computer's local time. To test, change your computer time and it will reflect in new Date 回答2: It'll use the time on whatever computer is running the code. In most cases, that's in a web browser on a client computer, so it'll use whatever time the web browser sees. This is most likely the computer's local time (unless the browser is doing something weird,

问题 This may be a dumb question, I'm 99% sure it does, but I need to be sure... does JS use the local computer's time? 回答1: Yes it does use the computer's local time. To test, change your computer time and it will reflect in new Date 回答2: It'll use the time on whatever computer is running the code. In most cases, that's in a web browser on a client computer, so it'll use whatever time the web browser sees. This is most likely the computer's local time (unless the browser is doing something weird,

问题 Consider the following code which attempts to get a DateTime that's equivalent to the local time "midnight yesterday": DateTime midnightYesterday = DateTime.Today.AddDays(-1.0d); Will this always result in a DateTime with a time component of 00:00:00 -- regardless of any corner cases such as leap days, leap seconds, or what the local time zone is? More generally: Does calling DateTime.AddDays , passing a whole number as a parameter, always result in a DateTime being returned that has the

问题 Consider the following code which attempts to get a DateTime that's equivalent to the local time "midnight yesterday": DateTime midnightYesterday = DateTime.Today.AddDays(-1.0d); Will this always result in a DateTime with a time component of 00:00:00 -- regardless of any corner cases such as leap days, leap seconds, or what the local time zone is? More generally: Does calling DateTime.AddDays , passing a whole number as a parameter, always result in a DateTime being returned that has the