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Folks, i thought it should be straightforward but after a few hours poking around, I decided it's best to post my question on this list. I have a data frame consisting of a (large) number of date columns, which are read in from a csv file as character string. I want to convert them to Date type. Following is an example, where the first column is of integer type, while the rest are type

Hi! I have a table with visits with a visited_at: attribute which is a datetime field. They seem to be stored as UTC. Now I want to count all visits each day and return something like: { 2013-01-01: 8, 2013-01-02: 4, 2013-01-07: 9, ... } So, I did it like this which kind of works...: def self.total_grouped_by_day(start_date, end_date) visits = where(visited_at:

Dear all; I am searching for a way to extract wind direction and speed from a wind rose plot. I have a graph and I want to make a dataframe of 5 years with hourly intervals. > start_date <- as.POSIXct("2019-01-01 00:00:00") > end_date <- as.POSIXct("2023-12-31 23:00:00") > time_sequence <- seq(from = start_date, to = end_date, by = "hour") > df

Hello It seems that datetime_select, is creating an instance of the Time class. Why would that be? I found this while building a site where people can create vigils (prayer vigils, peace vigils, etc). When I added a validation method that compared start_date to created_at, it generated the error: ArgumentError (comparison of Time with DateTime failed): I was able to put a breakpoint in the

I have the code for computing a weekly event: (start_date..end_date).select{|d| d.wday == wday} but I am wondering if anyone has any ideas for using this to figure out a recurring event for every other week. Is it possible to somehow specify every other within the .select method? Any other implementation ideas? --~--~---------~--~----~------------~-------~--~----~ You received this message

I have 3 models, class Host ref: string address: string, name: string primary_key=''ref'' has_many :rooms, :class_name=>"Room", :foreign_key=>''host_ref'' Class Room ref :string host_ref: string capacity: integer primary_key=''ref'' has_many

A wind rose plot omits time information. Your request is simply not possible. On October 30, 2024 3:48:03 AM PDT, javad bayat <j.bayat194 at gmail.com> wrote: >Dear all; >I am searching for a way to extract wind direction and speed from a wind >rose plot. I have a graph and I want to make a dataframe of 5 years with >hourly intervals. > >> start_date <-

Hi all, I have a situation with a recurring billing application where I need to test if one range of dates "overlaps" another range of dates. Does anyone know a rails find or mysql select statement that will test for this? Here are the details: * Recurringcharge items have a start_date and an end_date that represent the period of time that the charges should occur. * Statement items

I''m running into an issue undefined local variable or method `directoryid'' for #<EditorialsController:0x23f1bf8> I have two Models on a legacy database and only one controller called editorials with two actions index and display. I''m trying to pass in a parameter from the results of my search and getting the above error. Example: two tables one is editorial the

I am building an application and I have generated the scaffold for a product. In the list method I include something like my_date = Datetime.now and the result I get from the webrick is an error uninitialized constant Datetime Do I have to add a line with a require? I am new at ruby on rails thanks in advance -- Posted via http://www.ruby-forum.com/.

I''ve run into an interesting issue. When setting up a table with data from a file (I''m doing this in a block). I find that I can''t create separate entries manually after the import. It complains about a duplicate primary key. I''ve tried Schedule.id += 1 but id= either isn''t defined or accessible in the class Here is my code:

Rahul Agarwal Analyst Equities Quantitative Research UBS_ISC, Hyderabad On Net: 19 533 6363 hi let me explain you the problem we have a database which is in this format Stocks 30-Jan-08 28-Feb-08 31-Mar-08 30-Apr-08 a 1.00 3.00 7.00 3.00 b 2.00 4.00 4.00 7.00 c 3.00 8.00 655.00 3.00 d 4.00 23.00 4.00 5.00 e 5.00 78.00 6.00 5.00 and we have a query

Hi! If i have 2 tables i.e. product and images and product has_many images, image belongs_to product - how to create _form.rhtml, new/create and edit/update methods in product controller, so in a single form i can add one product and MANY (let''s assume for now that this number is fixed) images for this product? Pleeeeease help me :) -- Posted via http://www.ruby-forum.com/.

I''m using accepts_nested_attributes as follows: class Timesheet < ActiveRecord::Base attr_accessible :status, :user_id, :start_date, :end_date, :activities_attributes has_many :activities, dependent: :destroy has_many :time_entries, through: :activities accepts_nested_attributes_for :activities, allow_destroy: true end class Activity < ActiveRecord::Base attr_accessible

Hello, I need some help with designing a model I have in mind. I''m not sure what the best way to do it in Ruby/Rails is, or even if what I''m thinking is possible. Basically, I have a system where I want to treat everything as a "message." A Message is a basic model object with a title and message_text. It can stand on it''s own, or it can be

Hi R help forum, I have a simple data frame of four columns - one of numbers (really a categorical variable), one of dates and one of data. I have over 500,000 data points to work with, spread over 40 files, each named after a different animal. These are contact data recorded by proximity loggers over two years between the animals of the file name and collars being worn by other animals. The

Hi all, I have a simple data frame of three columns - one of numbers (really a categorical variable), one of dates and one of data. Imagine: collar date data 1 01/01/2013 x 2 02/01/2013 y 3 04/01/2013 z 4 04/01/2013 a 5 07/01/2013 b The 'collar' is a GPS collar that's been worn by an animal for a certain amount of time, and then may have been worn by a different animal after

Hi I have to create a json date like {"startDate":"\/Date(1291145744713-0700)\/","endDate":"\/Date(1293824144713-0700)\/"} This is just an example. My case startdate = Time.now-2.day enddate = Time.now I dont know how to convert this to the above format. Please help Thanks -- Posted via http://www.ruby-forum.com/. -- You

I''m having a little trouble with understanding how to work out the schematic for some of my classes using ActiveRecord when a file is in my lib directory: Brief example: Here''s the outline of the files in use: ....app ........controllers ............application_controller.rb ............rushing_offenses_controller.rb ........models ............rushing_offense.rb ....lib

I currently have a model that simply contains one datetime field: class CreateElectricityReadings < ActiveRecord::Migration def self.up create_table :clocks do |t| t.datetime :time_keeper t.timestamps end end def self.down drop_table :clocks end end If I enter the date string "13/10/2010" into this field its showing up in the controller as