I'm new to julia, but not so new on Dash; I'm trying to build my first app with Dash for julia, but I can't seem to make a pattern matching callback work properly. Here's the part of the code that's giving me troubles:
callback!(
app,
Output((type= "filter_", index= ALL), "options"),
Input("inputs", "data"),
State((type= "filter_", index= ALL), "value"),
) do inputs, filters
list_outs = []
list_vals = []
for i in 1:length(filters)
push!(list_outs, [(label= input, value= input) for input in inputs])
end
return list_outs
end
What I'm trying to do here is to use the available inputs of the data set, already stored in "inputs", to set the filters' options, creating as many sets of options as there are dropdowns.
The problem here is, I guess, in the format of the output I'm returning: it says "Invalid number of output values for {"index":["ALL"],"type":"filter_"}.options. Expected 3, got 1"
Sadly, I found nothing of use about how to use pattern matching callbacks with julia; I tried passing the output both as an array and as a tuple, but to no avail.
Any help is welcomed, thank you all!
This is the error related to the fact that if the result is a single Output, the callback output is automatically represented as an array of what is returned for uniform further processing. I.e., in your case, as [list_outs]. The fact that the Output with the match pattern is also treated as a single one is my bug, I added the issue and try to fix it in the near future.
Right now you can work around this problem by using Output as an array:
using Dash
using DashHtmlComponents
using DashCoreComponents
app = dash()
app.layout = html_div() do
dcc_input(id = "input", value = "A,B,C"),
dcc_dropdown(id = (type="filter_", index = 1)),
dcc_dropdown(id = (type="filter_", index = 2)),
dcc_dropdown(id = (type="filter_", index = 3)),
dcc_dropdown(id = (type="filter_", index = 4))
end
callback!(
app,
[Output((type= "filter_", index= ALL), "options")], #This is multiple output in explicitly form
Input("input", "value"),
State((type= "filter_", index= ALL), "value"),
) do input, filters
inputs = split(input, ",")
list_outs = []
list_vals = []
for i in 1:length(filters)
push!(list_outs, [(label= input, value= input) for input in inputs])
end
return [list_outs] # Accordingly, we return the result inside an additional array
end
run_server(app, debug = true)
Related
I have a string containing several elements, some identical and some unique. I want my code to check every 2 following elements in my string and if they're equal, it should call a function ShuffleString, where the input variable (randomize) is the string itself, that will re-shuffle the string in a new position. Then, the script should re-check every 2 following elements in the string again until no two identical elements appear next to each other.
I have done the following:
My function file ShuffleString works fine. The input variable randomize, as stated earlier, contains the same elements as MyString but in a different order, as this was needed on an unrelated matter earlier in the script.
function [MyString] = ShuffleString(randomize)
MyString = [];
while length(randomize) > 0
S = randi(length(randomize), 1);
MyString = [MyString, randomize(S)];
randomize(S) = [];
end
The script doesn't work as intended. Right now it looks like this:
MyString = ["Cat" "Dog" "Mouse" "Mouse" "Dog" "Hamster" "Zebra" "Obama"...
"Dog" "Fish" "Salmon" "Turkey"];
randomize = MyString;
while(1)
for Z = 1:length(MyString)
if Z < length(MyString)
Q = Z+1;
end
if isequal(MyString{Z},MyString{Q})
[MyString]=ShuffleString(randomize)
continue;
end
end
end
It just seems to reshuffle the string an infinite amount of times. What's wrong with this and how can I make it work?
You are using an infinite while loop that has no way to break and hence it keeps iterating.
Here is a simpler way:
Use the third output argument of the unique function to get the elements in numeric form for easier processing. Apply diff on it to check if consecutive elements are same. If there is any occurrence of same consecutive elements, the output of diff will give at least one zero which when applied with negated all will return true to continue the loop and vice versa. At the end, use the shuffled indices/numeric representation of the strings obtained after the loop to index the first output argument of unique (which was calculated earlier). So the script will be:
MyString = ["Cat" "Dog" "Mouse" "Mouse" "Dog" "Hamster" "Zebra" "Obama"...
"Dog" "Fish" "Salmon" "Turkey"]; %Given string array
[a,~,c] = unique(MyString);%finding unique elements and their indices
while ~all(diff(c)) %looping until there are no same strings together
c = ShuffleString(c); %shuffling the unique indices
end
MyString = a(c); %using the shuffled indices to get the required string array
For the function ShuffleString, a better way would be to use randperm. Your version of function works but it keeps changing the size of the arrays MyString and randomize and hence adversely affects the performance and memory usage. Here is a simpler way:
function MyString = ShuffleString(MyString)
MyString = MyString(randperm(numel(MyString)));
end
I know that, inside a MATLAB function, inputname(k) will return the k-th argument iff the argument is a variable name. Is there any way to write some parsing code that can retrieve the full input argument when that argument is a structure, e.g. foo.bar ? The reason I want to be able to do this is that I'm writing some tools for generic use where the input could be either a named variable or a named structure element.
My primary intent is to be able to store and return the input argment(s) as part of a structure or other variable that the function returns. This is a 'chain of custody' feature which makes it easier for me or others to verify the source data sets used to generate the output data sets.
I don't want the user to have to self-parse externally, or to have to deal with some kludge like
function doit(name,fieldname)
if(exist('fieldname','var'))
name = name.(fieldname);
myinput = [inputname(1),inputname(2)];
else
myinput = inputname(1);
end
% do the function stuff
(I call this a kludge because it both requires the user to enter strange arguments and because it fouls up the argument sequence for functions with multiple inputs)
There is no support from the language to get the input names when passing structs. The reason is probably x.a is internally a call to subsref which returns a new variable, all context is lost. The only possibility you have is using the debug tools and parse the code. There is no other option.
function x=f(varargin)
[ST, I] = dbstack('-completenames', 1);
if numel(ST)>0
fid=fopen(ST(1).file,'r');
for ix=2:ST(1).line;fgetl(fid);end
codeline=fgetl(fid);
fclose(fid);
fprintf('function was called with line %s\n',codeline);
else
fprintf('function was called from base workspace\n');
end
end
From there you may try to parse the code line to get the individual argument names.
Far uglier than Daniel's approach, and probably will crash on the wrong OS, but here's a hack that works to retrieve the first argument; easily adjusted to retrieve all arguments.
[~,myname] = system('whoami');
myname = strtrim(myname(4:end)); % removes domain tag in my Windows envir
% sorry about " \' " fouling up SO's color parsing
myloc = ['C:\Users\' , myname , '\AppData\Roaming\MathWorks\MATLAB\R2015a\History.xml'] ;
f = fopen(myloc,'r');
foo = fscanf(f,'%s');
fclose(f);
pfoo = findpat(foo,'myFunctionName');
% just look for the last instance
namstart = find(foo(pfoo(end):(pfoo(end)+30)) =='(',1) +pfoo(end);
% catch either ')' or ','
namend(1) = find(foo((namstart):end)== ')',1) -2 +namstart;
if numel(find(foo((namstart):end)== ',',1)),
namend(2) = find(foo((namstart):end)== ',',1) -2 +namstart;
end
thearg = foo(namstart:(min(namend)) );
I'm having trouble figuring out how to count the occurrences of a character in a string within a cell. For example, I have a file that contains information like so:
type
m
mmNs
SmNm
and I'm trying to determine how many m's are in each line. To do this, I've tried this code:
sampleddata = dataset('file','sample.txt','Delimiter','\t');
muts = sampleddata.type;
fileID = fopen('number_occur.txt','w');
for j = 1:3
mutations = muts(j)
M = length(find(mutations == 'm'));
fprintf(fileID, '%1f\n',M)
end
fclose(fileID)
However, I get an error that informs me: "Undefined operator '==' for input arguments of type 'cell'." Does anyone know how to overcome this problem?
Gonna post a result here in case you did not find a way to do it. There are loads of ways to do it, I am just going to put one of them.
Basically, you want a regex to do string matches:
a = {'type';
'm';
'mmNs';
'SmNm';
'mmmmM'} %//Load in Data,
pattern = 'm'; %//The pattern you are looking for is 'm', it could be anything really, a number of specific word or a specific pattern
lines = regexp(a, pattern, 'tokens'); %// look for this pattern in each line
result = cellfun('length',lines); %//count the size of matched patterns, so each time it matches, the size should increase by 1.
This gives the result in a matrix form:
result =
0
1
2
2
4
I'm attempting to make a program (for homework) which reads in a file, and then counts the number of times each word is used. For tackling the issue efficiently, I've decided to map all unique words to keys, and then increment the key value each time the word comes up.
function [] = problem2
file_open = fopen('austen.txt');
complete_string = textscan(file_open, '%s');
numel(complete_string{1,1})
unique_words = unique(complete_string{1,1});
length(unique_words);
frequency = zeros(numel(unique_words), 1);
found_frequency = containers.Map(unique_words, frequency);
for i=1:numel(complete_string{1,1})
found_frequency(complete_string{1,1}(i)) = found_frequency(complete_string{1,1}(i))+1;
end
fclose(file_open)
Sadly, this code does not work. When the line comes up to increment, I receive an error stating that "specified key type does not match the type expected for this container", which makes no sense to me - I'm using strings as the keys. Any ideas as to why I'm receiving this error?
The issue was in the use of Cell type - complete_String{1,1}(i) would actually return a Cell rather than a String (per spec, though). Wrapped it in char(*) and it worked fine.
I am attempting to loop through the variable 'docs' which is a cell array that holds strings, i need to make a for loop that colllects the terms in a cell array and then uses command 'lower' and unique to create a dictionary.
Here is the code i've tried sp far and i just get errors
docsLength = length(docs);
for C = 1:docsLength
list = tokenize(docs, ' .,-');
Mylist = [list;C];
end
I get these errors
Error using textscan
First input must be of type double or string.
Error in tokenize (line 3)
C = textscan(str,'%s','MultipleDelimsAsOne',1,'delimiter',delimiters);
Error in tk (line 4)
list = tokenize(docs, ' .,-');
Generically, if you get an "must be of type" error, that means you are passing the wrong sort of input to a function. In this case you should look at the point in your code where this is taking place (here, in tokenize when textscan is called), and doublecheck that the input going in is what you expect it to be.
As tokenize is not a MATLAB builtin function, unless you show us that code we can't say what those inputs should be. However, as akfaz mentioned in comments, it is likely that you want to pass docs{C} (a string) to tokenize instead of docs (a cell array). Otherwise, there's no point in having a loop as it just repeatedly passes the same input, docs, into the function.
There are additional problems with the loop:
Mylist = [list; C]; will be overwritten each loop to consist of the latest version of list plus C, which is just a number (the index of the loop). Depending on what the output of tokenize looks like, Mylist = [Mylist; list] may work but you should initialise Mylist first.
Mylist = [];
for C = 1:length(docs)
list = tokenize(docs{C}, ' .,-');
Mylist = [Mylist; list];
end