I'm new to D3.
I have a string stored in a var, below is the var.
var expense = {"name":"jim","amount":34,"date":"11/12/2015"};
and I want to only show the year of the date.
var parser = d3.timeParse("%Y");
expense.date = parser(expense.date);
console.log(expense);
but I am just getting null for the date. Anyone know how to fix this? I should get the result:
{name: "jim", amount: 34, date: 2015 }
If you want to use d3 date tools, first you have the parse your string to date format
const tParser = d3.timeParse("%d/%m/%Y")
then use on your string
const date = tParser(expense.date)
then use d3.timeFormat("%Y")
const year = d3.timeFormat("%Y")(date)
Or much simpler just split your string as rioV8 commented
expense.date = +expense.date.split('/')[2]
Thought it could be useful to know how to use d3 time format works, more info
Related
I assume I would need to change query in order to sort the data with today's date.
Please tell me how to change it though...
SQL QUERY in ToDoDao
#Query("SELECT * FROM todo_table WHERE date(date) = date('now')")
fun getTodayList(): Flow<List<ToDoTask>>
DATABASE
#Entity(tableName = DATABASE_TABLE)
data class ToDoTask(
#PrimaryKey(autoGenerate = true) val id: Int = 0,
#ColumnInfo(name = "title") val title: String,
#ColumnInfo(name = "description") val description: String,
#ColumnInfo(name = "priority") val priority: Priority,
#ColumnInfo(name = "date") val date: String,
#ColumnInfo(name = "favorite") var favorite: Boolean)
date val in ViewModel class
val date : MutableState<String> = mutableStateOf("")
datas inserted
enter image description here
I have tried the code below and I was able to activate the function as the query as I intented, so I think the query is the issue here.
#Query("SELECT * FROM todo_table WHERE date = '2023-2-14'")
fun getTodayList(): Flow<List<ToDoTask>>
The Issue
The issue is that the SQLite date function expects the date to be in an accepted format.
YYYY-M-DD is not such a format and will result in null rather than a date. YYYY-MM-DD is an accepted format (see https://www.sqlite.org/lang_datefunc.html#time_values). That is leading zeros are used to expand single digit numbers to 2 digit numbers for the month and day of month values.
The Fix (not recommended)
To fix the issue you have shown, you could use (see the However below):-
#Query("SELECT * FROM todo_table WHERE date(substr(date,1,5)||CASE WHEN substr(date,7,1) = '-' THEN '0' ELSE '' END ||substr(date,6)) = date('now');")
If the month was 2 numerics i.e. MM (e.g. 02 for February) then the above would not be necessary.
The CASE WHEN THEN ELSE END construct is similar to IF THEN ELSE END. see https://www.sqlite.org/lang_expr.html#the_case_expression. This is used to add the additional leading 0, when omitted, to the string used by the date function.
However, the above would not cater for days that have the leading 0 omitted for the first 9 days of the month. This due to the 4 permutations of the format (YYYY-MM-DD, YYYY-MM-D, YYYY-M-D and YYYY-M-DD) would be more complex e.g.
#Query("SELECT * FROM todo_table WHERE date(CASE WHEN length(date) = 8 THEN substr(date,1,5)||'0'||substr(date,6,1)||'-0'||substr(date,8) WHEN length(date) = 9 AND substr(date,7,1) = '-' THEN substr(date,1,5)||'0'||substr(date,6) WHEN length(date) = 9 AND substr(date,8,1) = '-' THEN substr(date,1,8)||'0'||substr(date,9) ELSE date END) = date('now');")
Recommended Fix
The recommended fix is to store values using one of the accepted formats rather than try to manipulate values to be an accepted date to then be worked upon using the date and time functions.
In My streamBuilder I have Array list contains dates having format(dd-MM-yyyy).
I want to arrange the list in ascending order.
The code I used in StreamBuilder after getting Datasnapshot
Map<dynamic, dynamic> data = snap.data.snapshot.value;
List item = [];
data.forEach(
(index, data) => item.add(
{"key": index, ...data}
)
);
item..sort((a,b)=>a['key'].compareTo(b['key']));
I am expecting result as
16-06-2020
17-06-2020
18-06-2020
19-06-2020
22-06-2020
04-07-2020
The result I am getting is
04-07-2020
16-06-2020
17-06-2020
18-06-2020
19-06-2020
22-06-2020
You'll need to parse your Strings to DateTimes. Since DateTime parse() method won't accept Strings in the format you provided, you can do something like this:
List<String> strings = ['04-07-2020', '17-06-2020', '16-06-2020', '19-06-2020', '18-06-2020', '22-06-2020'];
List<DateTime> dateTimes = [];
strings.forEach((string) {
var splitted = string.split('-');
var day = splitted[0];
var month = splitted[1];
var year = splitted[2];
var formatted = '$year-$month-$day';
dateTimes.add(DateTime.parse(formatted));
});
dateTimes.sort((a, b) => a.compareTo(b));
Just adapt it for your structure!
Storing the data as Timestamps in Firebase would make it much simpler, then you can sort it by this Timestamp.
If you need the dates formatted as a String (dd-MM-yyyy) you can just parse it to Datetime and use the Intl-Package to convert it to a formatted String.
My timestamp returns Timestamp(seconds=1560523991, nanoseconds=286000000) in a Flutter Firestore snapshot.
I want to print it as properly formatted date and time.
I'm using DateTime.now() to store current DateTime in Firestore while creating new records and retrieving it using Firestore snapshot but I am not able to convert to into formatted date time. I'm using lib intl.dart for formatting.
Code for saving data
d={'amount':amount,
'desc':desc,
'user_id':user_id,
'flie_ref':url.toString(),
'date':'${user_id}${DateTime.now().day}-${DateTime.now().month}-${DateTime.now().year}',
'timestamp':DateTime.now()
return Firestore.instance.collection('/data').add(d).then((v){return true;
}).catchError((onError)=>print(onError));
});
Accessing with
FutureBuilder(
future: Firestore.instance
.collection('data')
.where('user_id', isEqualTo:_user_id)
.getDocuments(),
builder: (BuildContext context,
AsyncSnapshot<QuerySnapshot> snapshot) {
if (!snapshot.hasData)
return Container(
child: Center(child: CircularProgressIndicator()));
return ListView.builder(
itemCount: snapshot.data.documents.length,
itemBuilder: (BuildContext context, int index) {
return Column(
children: <Widget>[
Text(DateFormat.yMMMd().add_jm().format(DateTime.parse(snapshot.data.documents[index].data['timestamp'].toString())]);
....
Error thrown is
Invalid date format.
I'm expecting output is: 'Jan 17, 2019, 2:19 PM'
When we push the DateTime object to Firestore, it internally converts it to it's own timestamp object and stores it.
Method to convert it back to Datetime after fetching timestamp from Firestore:
Firestore's timestamp contains a method called toDate() which can be converted to String and then that String can be passed to DateTime's parse method to convert back to DateTime
DateTime.parse(timestamp.toDate().toString())
Here is way!
Firestore will return TimeStamp like Timestamp(seconds=1560523991, nanoseconds=286000000).
This can be parsed as
Timestamp t = document['timeFieldName'];
DateTime d = t.toDate();
print(d.toString()); //2019-12-28 18:48:48.364
You can directly convert the Firestore timestamp object to DateTime like this:
DateTime myDateTime = (snapshot.data.documents[index].data['timestamp']).toDate();
This will return your Firestore timestamp in the dart's DateTime format. In order to convert your DateTime object you can use DateFormat class from intl package.
You can use your obtained DateTime object to get the format of your choice like this:
DateFormat.yMMMd().add_jm().format(myDateTime);
This code produces an output like this:
Apr 21, 2020 5:33 PM
timestamp parameter is the time in seconds
String formatTimestamp(int timestamp) {
var format = new DateFormat('d MMM, hh:mm a');
var date = new DateTime.fromMillisecondsSinceEpoch(timestamp * 1000);
return format.format(date);
}
Please check this answer for intl date formats
Hope it helps !
I found Ashutosh's suggestion gives more user friendly output. A function like this is recommended in a helper class with a static method.
static convertTimeStamp(Timestamp timestamp) {
assert(timestamp != null);
String convertedDate;
convertedDate = DateFormat.yMMMd().add_jm().format(timestamp.toDate());
return convertedDate;
}
Intl package is require for DateFormat.
Once you've got a timestamp back from Firestore, something like
Timestamp(seconds=1560523991, nanoseconds=286000000)
you need to parse it into an object of type DateTime:
DateTime myDateTime = DateTime.parse(timestamp.toDate().toString());
print('$myDateTime');
This will give you something like:
2020-05-09 15:27:04.074
You can then format myDateTime like this:
String formattedDateTime =
DateFormat('yyyy-MM-dd – kk:mm').format(myDateTime);
print('$formattedDateTime');
That will give you:
2020-05-09 – 15:27
Use intl package:
Timestamp firebaseTimestamp = ...;
var date = firebaseTimestamp.toDate();
var output1 = DateFormat('MM/dd, hh:mm a').format(date); // 12/31, 10:00 PM
var output2 = DateFormat.yMMMd().format(date); // Dec 31, 2000
You will get a unix timestamp from firestore even if you send a DateTime to firestore.
You can parse a DateTime from Firestore with DateTime.fromMillisecondsSinceEpoch(timestamp * 1000);
The DateTime class has two option to return a sting. toIso8601String() or toString()
choose the one you need. Or use eg. DateTime.now().hour; to get the our and create your own output.
For more information: Check https://api.dartlang.org/stable/2.4.0/dart-core/DateTime-class.html
Using cloud firestore, Here's my what worked for me:
Text(snapshot.data["YouKey"].toDate().toString().substring(0,16))
subString is optionnal, I've added it because I had the clock time with many number after the minute (like 12:00 00:00:00)
It took a long time to find the perfect answer.
When you fetch the data from Firestore as a Timestamp object and you are sure about that then I will recommend you use the following code:
DateTime fetchedDate = e.data()["deadline"]?.toDate();
using ?.toDate() worked for me and hopefully will also work for you.
Timestamp t = document['time'] // Timestamp(seconds=1624653319,nanoseconds=326000000)
DateTime d = t.toDate();
print(d.toString()); //2021-06-25 18:48:48.364
Do like so:
DateFormat.yMMMd().add_jm().format(DateTime.parse(snapshot.data.documents[index].data['timestamp'].toDate().toString())]
First visit here for intl package,
then paste the package into your pubspec.yaml, run pub get (the usual way of updating pubspec).Import the package into your dart file and try out the below method.
String timestamp;
DateTime now = DateTime.now();
String formatDate =
DateFormat('yyyy-MM-dd – kk:mm').format(now);
timestamp = formatDate;
You should use fromMillisecondsSinceEpoch function.
var d = new DateTime.fromMillisecondsSinceEpoch(ts, isUtc: true);
Here ts is int type.
So we can convert Firebase timestamps to DateTime object as follows.
DateTime date = DateTime.fromMillisecondsSinceEpoch(timestamp.seconds * 1000);
Simple way to solve it.
//Declare a variable Timestamp and assign the value timestamp from database
Timestamp timestamp = document['timeFieldName'];
//Use DateTime's parse method to convert back to DateTime
DateTime _time =DateTime.parse(timestamp.toDate().toString())
//Use this method to get the H:m of the DateTime.
//You can choose the DateFormat you want.
String readTimeStamp(DateTime date)
{
var format =new DateFormat.Hm(); // My Format 08:00
return format.format(date);
}
There are different ways this can be achieved based on different scenario, see which of the following code fits your scenario.
Conversion of Firebase timestamp to DateTime:
document['timeStamp'].toDate()
(document["timeStamp"] as Timestamp).toDate()
DateTime.fromMillisecondsSinceEpoch(document['timeStamp'].millisecondsSinceEpoch);
Timestamp.fromMillisecondsSinceEpoch(document['timeStamp'].millisecondsSinceEpoch).toDate();
If timeStamp is in microseconds use:
DateTime.fromMicrosecondsSinceEpoch(timestamp * 1000000);
If timeStamp is in milliseconds use:
DateTime.fromMillisecondsSinceEpoch(timestamp * 1000);
Add the following function in your dart file.
String formatTimestamp(Timestamp timestamp) {
var format = new DateFormat('yyyy-MM-dd'); // <- use skeleton here
return format.format(timestamp.toDate());
}
call it as formatTimestamp(document['timestamp'])
Note: To print this DateTime append toString()
I am using Java 8 to parse the the date and find difference between two dates.
Here is my snippet:
String date1 ="01-JAN-2017";
String date2 = "02-FEB-2017";
DateTimeFormatter df = DateTimeFormatter .ofPattern("DD-MMM-YYYY", en);
LocalDate d1 = LocalDate.parse(date1, df);
LocalDate d2 = LocalDate.parse(date2, df);
Long datediff = ChronoUnit.DAYS.between(d1,d2);
When I run I get the error:
java.time.format.DateTimeParseException: Text could not be parsed at index 3
First of all, check the javadoc. The uppercase D represents the day-of-year field (not the day-of-month as you want), and uppercase Y represents the week-based-year field (not the year as you want). The correct patterns are the lowercase letters d and y.
Also, you're using month names in uppercase letters (JAN and FEB), so your formatter must be case insensitive (the default behaviour is to accept only values like Jan and Feb). And these month names are English abbreviations, so you must also use English locale to make sure it parses the names correctly (using java.util.Locale class).
So, your formatter should be created like this:
DateTimeFormatter df = new DateTimeFormatterBuilder()
// case insensitive to parse JAN and FEB
.parseCaseInsensitive()
// add pattern
.appendPattern("dd-MMM-yyyy")
// create formatter (use English Locale to parse month names)
.toFormatter(Locale.ENGLISH);
This will make your code work (and datediff will be 32).
The following code works. The problem is you are using "JAN" instead of "Jan".
DateTimeFormatter does not recognize that it seems. and also change the pattern to
"d-MMM-yyyy".
String date1 ="01-Jan-2017";
String date2 = "02-Feb-2017";
DateTimeFormatter df = DateTimeFormatter.ofPattern("d-MMM-yyyy");
LocalDate d1 = LocalDate.parse(date1, df);
LocalDate d2 = LocalDate.parse(date2, df);
Long datediff = ChronoUnit.DAYS.between(d1,d2);
Source: https://www.mkyong.com/java8/java-8-how-to-convert-string-to-localdate/
// DateTimeFormatterBuilder provides custom way to create a
// formatter
// It is Case Insensitive, Nov , nov and NOV will be treated same
DateTimeFormatter f = new DateTimeFormatterBuilder().parseCaseInsensitive()
.append(DateTimeFormatter.ofPattern("yyyy-MMM-dd")).toFormatter();
try {
LocalDate datetime = LocalDate.parse("2019-DeC-22", f);
System.out.println(datetime); // 2019-12-22
} catch (DateTimeParseException e) {
// Exception handling message/mechanism/logging as per company standard
}
Maybe Someone is looking for this it will work with date Format like 3/24/2022 or 11/24/2022
DateTimeFormatter.ofPattern("M/dd/yyyy")
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("M/dd/yyyy");
formatter = formatter.withLocale( Locale.US ); // Locale specifies human language for translating, and cultural norms for lowercase/uppercase and abbreviations and such. Example: Locale.US or Locale.CANADA_FRENCH
LocalDate date = LocalDate.parse("3/24/2022", formatter);
System.out.println(date);
Maybe you can use this wildcard,
String d2arr[] = {
"2016-12-21",
"1/17/2016",
"1/3/2016",
"11/23/2016",
"OCT 20 2016",
"Oct 22 2016",
"Oct 23", // default year is 2016
"OCT 24", // default year is 2016
};
DateTimeFormatterBuilder builder = new DateTimeFormatterBuilder()
.parseCaseInsensitive().parseLenient()
.parseDefaulting(ChronoField.YEAR_OF_ERA, 2016L)
.appendPattern("[yyyy-MM-dd]")
.appendPattern("[M/dd/yyyy]")
.appendPattern("[M/d/yyyy]")
.appendPattern("[MM/dd/yyyy]")
.appendPattern("[MMM dd yyyy]");
DateTimeFormatter formatter2 = builder.toFormatter(Locale.ENGLISH);
https://coderanch.com/t/677142/java/DateTimeParseException-Text-parsed-unparsed-textenter link description here
Try using DateTimeFormatter dtf = DateTimeFormatter.ofPattern("dd-LLL-yyyy",Locale.ENGLISH);
I have a column (date) in csv which stores the date in "2003-02-01"(y-m-d). I would like to format the date in month and year like Apr 2003. how do i do that?
var format = d3.time.format("%m-%Y");
data.forEach(function(d,i) {
d.date = format(d.date);
});
I am getting the following error Error: TypeError: n.getFullYear is not a function Line: 5
the csv file contains values:
200,300,400,288,123,2003-01-01
300,700,600,388,500,2003-02-01
what is the issue here?
Javascript doesn't automatically recognize the values in the CSV file as dates, just reading them in as strings. d3's time functions make it pretty easy to convert them to datetime objects:
> parseDate = d3.time.format("%Y-%m-%d").parse
> parseDate('2003-01-01')
Wed Jan 01 2003 00:00:00 GMT-0600 (Central Standard Time)
To format the dates like you want, we need to go the other way, from a date object to a string:
> formatDate = d3.time.format("%b-%Y")
> formatDate(parseDate('2003-01-01'))
"Jan-2003"
I would recommend representing your dates within your program with date objects and only formatting them as strings when you need to display them.
D3 version 4 has different time methods now.
https://keithpblog.org/post/upgrading-d3-from-v3-to-v4/
https://github.com/d3/d3/blob/master/CHANGES.md
Your source date
var d = {created_time : "2018-01-15T12:37:30+0000"}
The structure of that date = %Y-%m-%dT%H:%M:%S%Z
I search google with "2018-01-15T12:37:30+0000" and it's suggestions provided the date structure string. Handy.
Create a timeParser to convert(parse) your date string into a date object
var parseDate = d3.utcParse("%Y-%m-%dT%H:%M:%S%Z")
//parseDate(d.created_time)
Now create a time formatter to return a formated date string for displaying.
var formatDate = d3.timeFormat("%b-%Y")
return formatDate(parseDate(d.created_time))
i.e.
Jan-1970
from Adam answer, here is a small helper function to convert a time string from a format to another:
var formatTime = function(input, formatInput, formatOutput){
var dateParse = d3.time.format(formatInput).parse;
var dateFormat = d3.time.format(formatOutput);
return dateFormat(dateParse(input));
};
use:
formatTime("2003-01-01", "%Y-%m-%d", "%b-%Y");
// output -> "Jan-2003"
if you are getting date lets say in variable " d = (e.g: '2003-03-01')" in string format then,
var monthNameFormat = d3.time.format("%b-%Y");
return monthNameFormat(new Date(d));
this will result date in "Jan-2003" format.
In D3Js v3, this worked for me:
var s = "2018-11-01T19:37:55Z";
d3.time.format("%Y-%m-%dT%H:%M:%SZ").parse(s);
// Thu Nov 01 2018 19:37:55 GMT-0700 (Pacific Daylight Time)