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Eric Sofen

Last seen: 2 dagen ago Active since 2018

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Answered
Sort rows of a table by column within a variable
There isn't a one-line solution to this, but here's another approach that hoists the data you want to sort by out of the table a...

16 dagen ago | 0

Answered
Frequency of unique items per month from timetable data
I think groupcounts will also solve your problem (it would be helpful to have some sample data in the question in a form I could...

ongeveer een maand ago | 0

Answered
Find locations of a value in 3-D matrix (lat x lon x time) and take the two time steps before and after those selected values
Since you're using lighting as a logical mask on the precipitation data, you can shift the array one or two time steps and re-ap...

10 maanden ago | 0

Answered
Rank stock returns by month
First off, get your dates into datetime rather than YYYYMM doubles! Then, you can use groupsummary to group the data by month a...

10 maanden ago | 0

Answered
Retime Yearly Maximum - Finding Corresponding Dates from Timetable
This example gives another way to get the time when the max occurred. See the findMax function and how it's used in rowfun. The ...

11 maanden ago | 1

Answered
How to extract specific dates from a datetime table?
If you know all the datetimes have 10:00:00 time components and you're just matching dates, timetable subscripting does that dir...

11 maanden ago | 2

Answered
Automatically create a several layer structure from a cell array
Another approach is to string this out into a table, converting what were labels along each dimension into grouping variables. S...

ongeveer een jaar ago | 0

Answered
Problems trying to find fakes dates.
The reason datetime(2005,2,29) works is that we want to support constructing a vector of datetimes: datetime(2023,1,1:100) Not...

ongeveer een jaar ago | 0

Answered
Case insensitivity for keys in outerjoin and ismember?
We've had a variety of requests for a "lenient" join, but there's also a variety of different interpretations of "lenient." :-) ...

ongeveer een jaar ago | 1

| accepted

Answered
How I can create a while cycle that ends after a sepecific time
I think timer is likely to give you better precision for this sort of thing than tic/toc (tic/toc is better for timing performan...

ongeveer een jaar ago | 0

Answered
convert cell array into date and time string
As much as I love string, there's no need to do an extra type conversion. Just concatenate the elements of the cell into a char ...

ongeveer een jaar ago | 0

Answered
Break array or timetable into smaller versions and find max value
Normally, groupsummary or varfun should be the starting point for grouped calculations like this, but your particuar problem is ...

ongeveer een jaar ago | 1

Answered
result in table format or excel format
It's a little circuitous, but you can use writelines to write the char vector to a text file, then use the power of readtable to...

ongeveer een jaar ago | 1

Answered
Merge tables with different columns and for matching columns update missing values in left table with values from right table
This is a tricky combination, and not doable in a single join right now. As you say, the outerjoin of A and C to create a table ...

meer dan een jaar ago | 0

Answered
How to extract all the data between two different dates?
I'd recommend using a timerange. Isbetween returns a logical vector based on a vector of datetimes. This can then be used to in...

meer dan een jaar ago | 1

Answered
How can I isolate and subplot June from the whole year?
Using datenum is no longer recommended. I'd encourage you to use datetime for date and time calculations in MATLAB. Among other ...

meer dan een jaar ago | 0

Answered
Creating Simulink dataset with timetable for importing in simulink signal editor
We're aware of this issue and have been working to reconcile it. The time vectors in Simulink and timetable are constructed in b...

meer dan een jaar ago | 0

Answered
Read netCDFs in loop and export to table with different sizes
I would suggest using timetable and the synchronize method. I assume nlevel is the sensor data? If so, build up a cell array of...

meer dan een jaar ago | 0

| accepted

Answered
divide year time data into days and nights
Steve beat me to it, but here's another solution that uses the datetime isbetween function. SunriseSunset = table((1:365)',date...

meer dan een jaar ago | 0

| accepted

Answered
Add code to have switch repeat if a case is not met
A while loop is one way to accomplish this. Also note that you can use lower() to reduce the number of cases. max_number = na...

meer dan een jaar ago | 0

Answered
Adding time to time string
Here's another slightly different approach. There's no need to replace "/" with "-" for datetime to parse it. Duration can parse...

meer dan een jaar ago | 0

Answered
Convert DoY and hour to datetime format
The datetime constructor is forgiving about day values that don't fit within a particular month and wrapping them appropriately:...

meer dan een jaar ago | 0

Answered
Compare table variables with input list and replace missing vars with NA
Readtable and outerjoin do the trick (xlsread is discouraged at this point - readtable is preferred). FYI, there's also a join L...

meer dan een jaar ago | 2

Answered
Sorting/Grouping based on date for all years
The isbetween function can also help simplify a lot of the logical indexing to pull out the ranges of interest. tt = readtime...

bijna 2 jaar ago | 1

Answered
How to make the following code valid for tables not only matrices
There are a few ways to rework the indexing to work with tables. By the way, I'm not sure what the loop does (ied doesn't appear...

bijna 2 jaar ago | 0

Answered
How do I find a single value by corresponding data in 2 different tables?
It sounds like you are trying to align these two things based on time? If so, check out the synchronize method of timetable. The...

ongeveer 2 jaar ago | 0

Answered
Replace string values in a table
This is what categorical is built for! When you create the categorical, you can specify the data, value set, and category names....

ongeveer 2 jaar ago | 0

Answered
How to extract table data based on column values?
One thing to watch out for is that the char vectors contained in the cell arrays (celltrs) can vary in the number of characters,...

ongeveer 2 jaar ago | 0

| accepted

Answered
I want to separate each gait cycle and keep each cycle in a row of a table.
If you separate each cycle into a separat row, the rows will likely have data of different lengths, which then gets hard to work...

meer dan 2 jaar ago | 0

| accepted

Answered
Problem with datetime in German
We’re aware of the issues with parsing month abbreviations in some locales, and we're looking at ways to improve this. In this c...

meer dan 2 jaar ago | 1

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