Is there a way to obtain the order of an ODE in mathematica.

For example, if i have `y''+5y`

i want mathematica return `2`

(beacuse it's a 2nd order equation). So, is it possible what i'm asking?

Is there a way to obtain the order of an ODE in mathematica.

For example, if i have `y''+5y`

i want mathematica return `2`

(beacuse it's a 2nd order equation). So, is it possible what i'm asking?

here is a way to extract the value automatically:

```
ode = y'' + y' + y == 0 ;
Max[Cases[ ode , Derivative[n_][y] :> n , Infinity]]
```

2

note this just finds the largest derivative in the expression, it doesn't verify if the expression is actually an ode..

You can pass a custom function to sort using the key parameter like this: from math import sqrt def get_ordered_list(points, x, y): points.sort(key = lambda p: sqrt((p.x - x)**2 + (p.y - y)**2)) return points ...

You can try lapply lapply(spmtcars, function(x) x[order(-x$mpg),]) ...

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python,wolfram-mathematica,sage

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algorithm,sorting,language-agnostic,order,priority

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After the usual lots of trial and error that WolframAlpha didn't understand, finally WolframAlpha PrimeOmegaPlot link...

Got it! I had already read the documentation before posting the question, but haven't had the click that lead me to the solution. This section on structuring data holds the answer: https://www.firebase.com/docs/ios/guide/structuring-data.html Understand: The natural structure would be: - champs - champID - matches - matchID - <matchData> - champName...

Since you are specifying the ordinal domain, dc.js will used that instead of calculating it using the existing values and the ordering you specify. Simply remove the domain and specify the ordering: .x(d3.scale.ordinal()) .ordering(function(kv) { return -kv.value; }) Fork of your fiddle: http://jsfiddle.net/0p78m8vr/6/...

wolfram-mathematica,wolfram-language

Switch may be useful, for example: Switch[ # , _String , StringLength[#] , _List , Length[#] , __ , Null ] & /@ { "abc", {1, 2, 3, 4}, Pi} {3, 4, Null} ...

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The thing to keep in mind is that Mathematica is formula-oriented and is programmed in terms of mathematical variables, while Matlab is numerically oriented and programmed in terms of matrices and arrays. To evaluate a function of two variables on a grid, it is necessary to first generate that grid...

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First you should create ActiveRecord class for video and likes tables to make things easier. The aim is to create the two following classes class Video extends \yii\db\ActiveRecord and class Likes extends \yii\db\ActiveRecord. To do it easily, you should look at gii utility which will do it for you (available...

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If you really need to apply different formatting, you can do it using a derived table: select DATENAME(MM, [date]) + ' ' + CAST(DAY([date]) AS VARCHAR(2)) AS [DD Month], total_quantity from ( SELECT CAST([Datetime] AS DATE) AS [date], SUM(quantity) as total_quantity FROM Invoice_Itemized ii INNER JOIN Invoice_Totals it ON it.Invoice_Number...

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The easiest way would be to pad the keys to a fixed length. e.g. 038,007 will be ordered before 038,012 But the padding length would have to be safe for the largest taskid. Although you could keep your path trimmed for readability and create an extra padded field for sorting....

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