I am trying to create an irregular volume scanner on Thinkorswim using Thinkscript. I want to create an array of volume's in past periods so that I can compare them to the current period's volume (using fold or recursion). However, while the Thinkorswim documentation details what is called an IDataHolder datatype, which is an array of data, I cannot find how one can actually create one, as opposed to just referencing the historical data held by Thinkorswim. Here is the documentation: https://tlc.thinkorswim.com/center/reference/thinkScript/Data-Types/IDataHolder
I have tried coding something as simple as this to initialize an array:
def array = [];
This throws an error. I have tried different types of brackets, changing any possible syntax issues, etc.
Is this possible in the Thinkscript language? If not, are there any workarounds? If not even that, is there a third party programming interface that I could use to pull data from Thinkorswim and get a scanner that way? Thanks for any help.
IDataHolder represents data such as close, open, volume, etc, that is held across multiple bars or ticks. You can reference one of these pre-defined data series, or you can create your own using variables: def openPlus5cents = open + 0.05, say, would be an IDataHolder type value.
There's no way to create an array in the usual programming sense, as you've found, so you'll have to be a little creative. Perhaps, say, you could do the comparison within the fold? volume[1] > volume, or the like? Maybe post another question with an example of the comparison you're trying to do?
Related
I am trying to create a new reference containing another reference as in ${var${randnum}}.
Ultimately, I want to create a variable which refers to a two times two randomized set of variables.
As the above approach did not work, I developed it further with below result.
In the calculate field I write
concat('$','{','trust',${rand_no2},'_' ,${rand_no3_1},'}')
Which should result in
${trust1_1}
and respective combinations.
Without line 11 (name=ref2) the file compiles and I can start it in ODK Collect (v.2.4) on my phone. When I reach line 10 (in ODK Collect), however, I receive the message:
"Error Occured
Dependency cycle in s; recursion limit exceeded!!"
(I included line 11 to show what I want to do in the end.)
I am writing the file in Excel and compile it with ODK xlsform offline. (For testing I transfer it via cable to my phone.)
The xls file for reproduction can be found here:
https://forum.getodk.org/t/concatenate-references-to-create-new-reference-var-randnum/34968
Thank you very much in advance!
You're mixing up some things related to the ${q} syntax, question names and question values.
Note that ODK Collect does not actually understand the ${q} syntax (which is XLSForm-only). It's helpful to look at the actual form format that ODK collect understands which is called XForm, an XML format that XLSForm converts into. However, even if ODK Collect understood the ${q} syntax, your approach still wouldn't work since you're creating a string value for the ref question (using concat). This wouldn't magically be evaluated as a reference / formula. You cannot dynamically create a reference or formula.
At the moment (until ODK supports something like the local-name() function), maybe the best approach is to use position and put the calculated values inside a group. Something like //group/calc[number(${pos})] perhaps. Note that positions are 1-based (so the first item is position 1) and casting the position to a number or integer is required.
The problem:
I need to read a row of values from an excel spreadsheet into a parameter array and use these values to set the initial values of stocks.
The specifics:
a. I can successfully set the scalar parameters default values from excel using ExcelControlName.getCellNumericValue("ExcelSheetName", RowNumber, ColumnNumber).
b. Trying to set default values for array parameters with ExcelControlName.readHyperArray(DestinationArrayName,"ExcelSheetName",RowNumber, ColumnNumber, false) returns a "Cannot return a void result" error on build.
c. I can read the parameter arrays from a function called from the Agent actions "On startup:" section using ExcelControlName.readHyperArray(DestinationArrayName,"ExcelSheetName",RowNumber, ColumnNumber, false).
d. Stocks with their initial values set to the parameter array that was successfully loaded by the function are all zero even though the parameter array shows values (when run). Initial value: ParameterArrayName.
e. When I set the parameter array values through the value editor the stocks initialize correctly.
My suspicion:
I'm thinking that the issue has something to do with the internal timing within the entrails of the model generated by Anylogic such that the function to load the parameters is executed after the stocks get initial values - but that could just be the delirium caused by repeatedly smashing my forehead into the wall. But, if this is indeed the case, how can I sneak the function in earlier or, better yet, how would someone who actually knows what they're doing accomplish this?
What I'm trying to accomplish:
As a septuagenarian with lots of time on my hands and a vague recollection of dynamic modeling using Dynamo from a Systems Science program in the early seventies (and not used since), I thought I'd take a whack at age-based modeling of the COVID-19 pandemic. I wanted to see, among other things, whether establishing elder-prisons (in now vacant Club-Meds, Sandals... I'm sure) would be an economically advantageous strategy. Getting there requires dis-aggregating classic SIR approaches into age-specific chains of causality. So far, I'm at 27 age-specific parameters for eight age-groups and 24 scalar parameters. As much as I'd like to type and retype... all this data I'm really hoping there is a better way.
I must say that I am amazed at how far modeling has come in only 50 or so years and I am enthralled with Anylogic's application - even though it's a bit java-ish for me.
Thank you ever so much,
Carl Cottrell
Equivalent parameter arrays - one with values entered in edit the other read from excel file through a function
Not sure if I understand but here it goes:
I understand that you have the following structure:
and you want to initialize the stock as follows.
To do that, on the initial value of your parameter use a function that returns an HyperParameter:
the function getInitialValue should return an HyperParameter and I think this code should work for you (you have to choose RowNumber according to whatever is on your excelfile, MyDimension is the name of your dimension, and ExcelControlName is the excel in which you hold the values of the initial values of the stock)
HyperArray x=new HyperArray(MyDimension);
for(int i=0;i<=numColumns;i++){
x.set(ExcelControlName.getCellNumericValue("ExcelSheetName", RowNumber, i), i);
}
return x;
I started coding in Smalltalk and got stuck here. I have this 2d array:
testArr := Array new: 1.
testArr at: 1
put: ((Array new: 3)
at: 1 put: '1A';
at: 2 put: '1B';
at: 3 put: '1C';
yourself).
But if I want to access lets say first element of first array, what should I write to make it happen?
Thanks!
I'm tempted to take advantage of your question & answer, and elaborate a little bit on knowledge that belongs in the Smalltalk folklore (which you may already be aware of).
As we progresses in the use of Smalltalk, we will likely note that the Array class starts to play a decreasing role in our models. Why is that? Because it takes time to find out which are the objects our models will produce; the balance between too many and too few is a delicate matter, mostly clueless at the beginning.
Arrays and their composition are handy data structures. However, they solve the problem of organizing data at the expense of dealing with it. If the client of such a structure needs to know how data is stored as a prerequisite to act on it, then the message paradigm becomes semantically idle.
Let's imagine a matrix object. There are several ways to keep their entries: a one-dimensional array, an array of rows, an array of columns, a dictionary of (sparse) non-null entries, a triangular structure if the matrices are known to be symmetric/anti-symmetric/Hermitian, and a lot more for special cases. Of course, this variety makes no sense for the problem at hand and, in any case, it would be a bad idea to spend time considering the most general approach: In Smalltalk, generality is attained at the message, not at the storage.
Regardless of the internal organization of data, our objects should always offer protocols that are independent of the underlying structure. Back to the matrix example, even if our initial organization is an array of rows, the matrix object should work the same whether rows are arrays or more sophisticated vector objects that are also used for other ends. This means that when coding the internal access to entry (i,j) we should pretend we don't know the class of row i but only the message to access its jth element. Something on the lines of
atRow: i column: j
| row |
row := self row: i.
^row at: j
Here we are not assuming that row is an Array; we are only assuming that it understands the at: message, which is the least we can assume when talking to a row object, whatever its actual nature. Of course, this code is only good under the assumption that rows are not recreated on the fly, as they would, had our class kept instead collections of columns. But this is ok, otherwise we would only need to add another class and override this and some few other low level messages.
In any case, the idea is to defer as much as possible any explicit knowledge about the internal organization so that it gets confined to a few private messages. One way to test we are applying this good practice is to make sure no low level code repeats in two or more methods. For instance, the use of the row: message above moves low level code away from atRow:column:, deferring it to another that makes sense for the (ideal) matrix protocol.
This example illustrates an important point: be suspicious of any code that needs to compose two at: messages. And --why not-- enjoy the beauty of not having to declare types.
So, the problem was in brackets.
^(testArr at: 1) at:1
returns
1A
as I needed.
I am doing a SPARQL Query that for one variable gives me the output "[-1.6101874126499998e-19]". This is obviously a string containing an array (that could also contain more numbers). Is there a way to access the number in it or does it need to be done in the underlying graph?
If it needs to be changed in the graph, what is a good ontological way to create multi-dimensional arrays...?
xsd:float(SUBSTR(?var,2,STRLEN(?var)-2)) does the job in this case, but it's quite hacky :/
In FMI 2.0, array parameters are serialized to scalar variables.
Importing tools can display them as arrays, but their size is fixed and their handling is inefficient.
Better array support is currently in development by a working group of the FMI project, but I would like to know about workarounds how to handle array parameters in the meantime.
Ideas are to
hard code them (disadvantage: the are no paramters any more ...)
put them in a CSV file in the resources folder and read them at the start of the simulation (disadvantage: no parameter mask support, complicated)
put them in a string parameter and parse it at simulation start (disadvantage: limited length of strings, complicated)
Are there other ideas / workarounds? Thanks in advance.
Combinations of the ideas outlined in your question are also possible.
Hard code with selector parameter
Here the idea is to hard code several variants of your array and allow the user to select one with a parameter.
I did this in a recent project where a user needed to choose between different spatially resolved initial conditions (e.g. temperature profiles). We used a model to generate more than 100 different sets of spatially resolved initial conditions (each representing a different "history" of the modeled object), hard coded them as FORTRAN arrays (the inner core of the FMU was in FORTRAN), and used a single integer parameter to select which profile he wanted to use.
It worked very well and the user has no way of breaking it.
Shorten the array and interpolate
If the data in your array is smooth, you might be able to dramatically reduce the number of values you actually need to pass to your simulation - which would make serialization into scalar parameters less painful.
Within the FMU, interpolate to get the resolution you need.
String parameter to select csv file
You can use a string parameter to provide the path to a user-provided csv-file. I would not recommend this, because the user will most likely break it.