6
votes
Accepted
Applying a function on several columns of a dataset fails on Missing
The issue
The problem is the structural difference between the two cases:
...
- 34.7k
6
votes
Fill a sequence containing missing values
Quite ugly, but might inspire someone to come up with a better solution:
...
- 34.7k
6
votes
Using ReactionBalance on chemical entities with missing formula
I don't know why "Diazine" is missing its formula, I will update the database and after the next knowledgebase update it should work.
It will work just ...
- 72.3k
5
votes
Accepted
How to accomodate empty data set in ListPlot, ListLinePlot?
setA = {{1, 2}, {3, 6}, {7, 5}};
setB = {};
ListPlot[{setA, setB} /. {} :> {Missing[]}, PlotLegends -> Automatic]
- 84.8k
5
votes
Accepted
Quickly checking Missing[] is only at the start of a list
This is quite fast:
missingOnlyAtStartOfData1[data_] :=
FreeQ[data[[LengthWhile[data, MissingQ] + 1 ;;]], _Missing];
My first thought was to refactor the OP's ...
- 259k
4
votes
4
votes
4
votes
Accepted
3
votes
Using ReactionBalance on chemical entities with missing formula
You can use ChemicalFormula instead of an entity.
...
- 41.5k
3
votes
Accepted
Missing["reason"] changes when Joined in a Tabular
For efficiency reasons Tabular stores a single type of Missing[...] internally, which is Missing["NotAvailable"] by default.
It is possible to extend the number of different Missing[...] ...
- 6,888
3
votes
Accepted
How to Export ragged data to a spreadsheet with missing variables in a way that the Mean calculations in both Mathematica and the Spreadsheet match
In Mathematica
Assume I have a file like below:
data1.csv
---------
1,2,3
0,,4
,,2
If you import the following file, it will replace empty cells with ...
- 9,669
3
votes
Accepted
Missing["reason"]—can any reason be used?
The documentation states, Missing is "a symbolic object, with no default evaluation rules defined". That means Missing is not a ...
- 109k
3
votes
How to Export ragged data to a spreadsheet with missing variables in a way that the Mean calculations in both Mathematica and the Spreadsheet match
The gist of your question seems to be how to find an identical representation for your data that is interpreted the same way in both Mathematica and some unidentified spreadsheet application.
First ...
- 39.6k
3
votes
Using TotalVariationFilter on dataset with missing data
This is a workaround in some cases. Imagine data:
data = {1, 3, 3, Missing[], 4, 3, 2};
TotalVariationFilter would not work:
...
- 74.9k
2
votes
Accepted
Using two functions to plot one function
FindRoot evidently is not finding all the values. You can set up your tables before using FindRoot.
...
- 8,588
2
votes
Handling Missing values flexibly in Query (MissingBehavior problem)
Within the Plus function Missing[...] only acts as if it were zero. Actually, it is taken to be ...
- 69.8k
2
votes
Accepted
Subtracting Missing[] the old way
You could try something like:
Unprotect[Missing];
Missing /: Plus[a_Missing, b__] := Indeterminate
Protect[Missing];
Your example:
...
- 133k
2
votes
Replacing values in a dataset
Look at the DisplayForm of the dataset first, it's not what you think.
Here's one way to do it:
...
- 31.9k
2
votes
Accepted
Specifying the position of the bottom element in a matrix when the last few elements are missing
rownum = LengthWhile[m, Length@# == 2 &]
2
m[[rownum, 2]]
...
- 403k
2
votes
Finding Missing Values in TimeSeries
You may use "ReplaceAll". Here are some examples:
To remove the missing entry entirely:
...
- 60.9k
2
votes
Accepted
Apply a function to a rectangular subgrid with missing values
mF[f_, rows_, columns_] := MapAt[
ReplaceAll[{m_Missing :> m, x_ :> f[x]}],
Tuples[{rows, columns}]]
Examples:
...
- 403k
2
votes
Is any function similar to SpanFromLeft and SpanFromAbove that actually imputes the values?
Searching through the documentation, it seems that only *Grid functions deal with Span* placeholders.
You can write your own ...
- 41.5k
1
vote
Accepted
Generalizing a function to ignore Missing
I think the variation you want to apply is to the functions, not to the data. A function like MovingAverage creates a shorter list just by the semantics of what a ...
- 39.6k
1
vote
ListPointPlot3D syntax for missing data
Oops, that was easy, just enter an empty list instead of Missing[]:
ListPointPlot3D[{{}, {{1, 3, 3}, {2, 4, 4}}}]
- 4,931
1
vote
1
vote
Accepted
1
vote
Plotting rescaled time series and temporal data
Your issue is caused by the way Mathematica's Plot function handles missing data. It assumes it to be eg. a potentially noisy dataset where interpolating could lead to false assumptions about the ...
- 1,017
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