r - How to calculate the number of a specific weekday between two POSIXct date arrays and return another numerical array? -


i wrote formula based on weekday calculating algorithm (found in stackexchange well, great job guys. here code snippet:

countwd <- function(start, end, day){   x <- seq(start, end, by=1)   y <- weekdays(x, true)   sum(y==day) } x$offday <- null for(i in 1:nrow(x)){   x$offday[i] <- countwd(x$pick_date[i], x$ship_date[i], "mon") }

this way slow (loop proceeds 2-4 rows per second!!!!), , have millions of entries each month.

here vectorisation of function:

x$offday <- countwd(x$pick_date, x$ship_date, "mon")

shows error:

error in seq.posixt(start, end, = 1) : 'from' must of length 1

i cannot understand how apply "apply" family functions in case have 2 vectors compare (yes, new this).

sample data:

pick_date   ship_date 01-apr-2017 00:51   02-apr-2017 06:55 01-apr-2017 00:51   02-apr-2017 12:11 pm 01-apr-2017 00:51   02-apr-2017 12:11 pm 01-apr-2017 00:51   02-apr-2017 09:39

i have converted these posixct, , formula works individual values (returns second value though, no idea why. however, can work around that):

>countwd(x$pick_date[1], x$ship_date[1], "mon") [1] 0

based on @demirev's answer , comments above, here worked example using improved countwd function , mapply. put in few helper columns using lubridate check solution, , changed of dates return values df$off_days not zero.

library(lubridate)  df <- data.frame(pick_date = c(rep("01-apr-2017 00:51", 4)), ship_date = c("05-apr-2017 06:55", "09-apr-2017 12:11", "30-apr-2017 12:11", "02-may-2017 12:11"))  df$pick_date <- lubridate::dmy_hm(df$pick_date) df$ship_date <- lubridate::dmy_hm(df$ship_date)  df$pick_day <- wday(df$pick_date, label = t) df$ship_day <- wday(df$ship_date, label = t) df$days_between <- interval(df$pick_date, df$ship_date) %/% days()  countwd <- function(start, end, day) {     x <- seq(start, end, by="day")     y <- weekdays(x, true)     sum(y==day) }  df$off_days <- mapply(countwd, df$pick_date, df$ship_date, "mon") df              pick_date           ship_date pick_day ship_day days_between off_days 1 2017-04-01 00:51:00 2017-04-05 06:55:00      sat      wed            4        1 2 2017-04-01 00:51:00 2017-04-09 12:11:00      sat      sun            8        1 3 2017-04-01 00:51:00 2017-04-30 12:11:00      sat      sun           29        4 4 2017-04-01 00:51:00 2017-05-02 12:11:00      sat     tues           31        5

Comments

Post a Comment

Popular posts from this blog

php - Vagrant up error - Uncaught Reflection Exception: Class DOMDocument does not exist -

i've set bento/ubuntu-16.04 vagrant box using php 5.6, , getting following error quite few times when try , run shell script: "uncaught reflection exception: class domdocument not exist". i've tried adding following top of script (not together), each no success: "sudo apt-get install php5.6-xml", "sudo apt-get install php5-xml", "sudo apt-get install php-dom" i've tried resetting server "sudo service apache2 restart". does have suggestions?
Read more

vue.js - Create hooks for automated testing -

Image
qa guys complained can't automate frontend testing. because our html looks same outside. lazy hack did this <template> <div :role="$options.name"> ... </div> </template> <script> export default { name: 'vmcomponentname' } </script> which takes name script , applies html. in browser get: <div role="vmcomponentname"> ... </div> line :role="$options.name" goes in every component. is there dry er solutions? please share. additional details i'll explain in details looking for. imagine have vmusercreate form creates user. test case can create user . to automatically test without role, have use following selector: .wrapper > .wrapper > .wrapper > .submit-button the test extremely brittle (will break lot). if use roles can use [role="vmusercreateform"] .submit-button selector. many folds less brittle. so basically, i'm ...
Read more

Add new key value to json node in java -

i have json file : { "id":1, "name":"abc", "addressdetails": { "city":"newyork" } } i wanted add 1 more key-value ("pincode" : "414141") node 'addressdetails'. i tried using : objectmapper mapper = new objectmapper(); jsonnode root = mapper.readtree(new file("d://test.json")); objectnode node = mapper.createobjectnode(); node.with("addressdetails").put("pincode", "414141"); but it's not getting added, there way can ? you can try you should modify file path objectmapper mapper = new objectmapper(); objectnode nodes = mapper.readvalue(new file("d:\\test.txt"), objectnode.class); nodes.with("addressdetails").put("pincode", "414141"); mapper.writer().writevalue(new file("d:\\test.txt"), nodes);
Read more