In the Help Documentation of Scilab 6.0.2, I can read the following instruction on the Overloading entry, regarding the last operation code "iext" showed in this entry's table:
"The 6 char code may be used for some complex insertion algorithm like x.b(2) = 33 where b field is not defined in the structure x. The insertion is automatically decomposed into temp = x.b; temp(2) = 33; x.b = temp. The 6 char code is used for the first step of this algorithm. The 6 overloading function is very similar to the e's one."
But I can't find a complete example on how to use this "char 6 code" to overload a function. I'm trying to use it, without success. Does anyone have an example on how to do this?
The code bellow creates a normal "mlist" as a example. Which needs overloading functions
A = rand(5,3)
names = ["colA" "colB" "colC"]
units = ["ft" "in" "lb"]
M = mlist(["Mlog" "names" "units" names],names,units,A(:,1),A(:,2),A(:,3))
Following are the overload functions:
//define display
function %Mlog_p(M)
n = size(M.names,"*")
formatStr = strcat(repmat("%10s ",1,n)) + "\n"
formatNum = strcat(repmat("%0.10f ",1,n)) + "\n"
mprintf(formatStr,M.names)
mprintf(formatStr,M.units)
disp([M(M.names(1)),M(M.names(2)),M(M.names(3))])
end
//define extraction operation
function [Mat]=%Mlog_e(varargin)
M = varargin($)
cols = [1:size(M.names,"*")] // This will also work
cols = cols(varargin($-1)) // when varargin($-1) = 1:1:$
Mat = []
if length(varargin)==3 then
for i = M.names(cols)
Mat = [Mat M(i)(varargin(1))]
end
else
for i=1:size(M.names(cols),"*")
Mat(i).name = M.names(cols(i))
Mat(i).unit = M.units(cols(i))
Mat(i).data = M(:,cols(i))
end
end
endfunction
//define insertion operations (a regular matrix into a Mlog matrix)
function ML=%s_i_Mlog(i,j,V,M)
names = M.names
units = M.units
A = M(:,:) // uses function above
A(i,j) = V
ML = mlist(["Mlog" "names" "units" names],names,units,A(:,1),A(:,2),A(:,3))
endfunction
//insertion operation with structures (the subject of the question)
function temp = %Mlog_6(j,M)
temp = M(j) // uses function %Mlog_e
endfunction
function M = %st_i_Mlog(j,st,M)
A = M(:,:) // uses function %Mlog_e
M.names(j) = st.name // uses function above
M.units(j) = st.unit // uses function above
A(:,j) = st.data // uses function above
names = M.names
units = M.units
M = mlist(["Mlog" "names" "units" names],names,units,A(:,1),A(:,2),A(:,3))
endfunction
The first overload (displays mlist) will show the matrix in the form of the following table:
--> M
M =
colA colB colC
ft in lb
0.4720517 0.6719395 0.5628382
0.0623731 0.1360619 0.5531093
0.0854401 0.2119744 0.0768984
0.0134564 0.4015942 0.5360758
0.3543002 0.4036219 0.0900212
The next overloads (extraction and insertion) Will allow the table to be access as a simple matrix M(i,j).
The extraction function Will also allow M to be access by column, which returns a structure, for instance:
--> M(2)
ans =
name: "colB"
unit: "in"
data: [5x1 constant]
The last two functions are the overloads mentioned in the question. They allow the column metadata to be changed in a structure form.
--> M(2).name = "length"
M =
colA length colC
ft in lb
0.4720517 0.6719395 0.5628382
0.0623731 0.1360619 0.5531093
0.0854401 0.2119744 0.0768984
0.0134564 0.4015942 0.5360758
0.3543002 0.4036219 0.0900212
Related
I'm trying to build a GUI to output plots for control system design when input parameters of transfer function.I got some problems on passing parameters to the function and changing variable type.
I've got a stucture with examples of simulation parameters:
param = [];
param.parameter = "s";
param.dom = "c"; //domain(c for continuous, d for discrete)
param.num = 1; //numerator of transfer function
param.den = "(s+1)^3"; //denominator
param.fmin = 0.01; //min freq of the plot
param.fmax = 100; //max freq
and a function to plot the graphs:
// display function
function displayProblem(param)
parameter = param.parameter;
dom = param.dom;
num = param.num;
den = param.den;
fmin = param.fmin;
fmax = param.fmax;
s = poly(0,parameter.string);
h = syslin(dom.string,num,den);
// Plotting of model data
delete(gca());
//bode(h,fmin1,fmax1);
gain_axes = newaxes();
gain_axes.title.font_size = 3;
gainplot(h,fmin,fmax);
gain_axes.axes_bounds = [1/3,0,1/3,1/2];
gain_axes.title.text = "Gain Plot";
phase_axes = newaxes();
gain_axes.title.font_size = 3;
phaseplot(h,fmin,fmax);
phase_axes.axes_bounds = [1/3,1/2,1/3,1/2];
phase_axes.title.text = "Phase Plot";
phase_axes = newaxes();
gain_axes.title.font_size = 3;
nyquist(h);
phase_axes.axes_bounds = [2/3,0,1/3,1/2];
phase_axes.title.text = "Nyquist Plot";
endfunction
There's something wrong when passing numerator and denominator to the function. The variable type doesn't match what syslin required. If I replace 'num' and 'den' with '1' and '(s+1)^3', everything worked quite well. Also if I try this line-by-line in control panel, it works, but not in SciNotes. What's the proper way to deal with this? Any suggestion will be greatly appreaciated.
There are 3 errors in your code: Replace
param.den = "(s+1)^3"; //denominator
with
param.den = (%s+1)^3;
Indeed, Scilab has a built-in polynomial type. Polynomials are not defined as a string nor as a vector of coefficients. The predefined constant %s is the monomial s.
In addition,
s = poly(0,parameter.string);
is useless (and incorrect: parameter would work, while parameter.string won't since parameter has no string field: It IS the string). Just remove the line.
As well, replace
h = syslin(dom.string,num,den);
with simply
h = syslin(dom, num,den);
Finally, although the figure's layout is not simple, you can use bode() in the function in the following way:
// delete(gca());
subplot(1,3,2)
bode(h, fmin, fmax)
subplot(2,3,3)
nyquist(h)
gcf().children.title.text=["Nyquist Plot" "Phase Plot" "Gain Plot"]
All in one, the code of your function may resume to
function displayProblem(param)
[dom, num, den] = (param.dom, param.num, param.den);
[fmin, fmax] = (param.fmin, param.fmax);
h = syslin(dom, num,den);
// Plotting of model data
subplot(1,3,2)
bode(h,fmin,fmax);
subplot(2,3,3)
nyquist(h);
gcf().children.title.text=["Nyquist Plot" "Phase Plot" "Gain Plot"];
endfunction
Best regards
I have a cell array of strings of length 3
headers_ca =
{
[1,1] = time
[1,2] = x
[1,3] = y
}
I want to create a struct that mimics a python dict, with the values in headers_ca as keys (fieldnames in Octave) and an initializer value ival for all entries.
It would be a struct, since even dict exists in octave, it has been deprecated.
I could do (brute force) s = struct("time", ival, "x", ival, "y", ival);
What is the most concise way to do this?
I know I can do a for loop.
Can it be avoided?
I would be working with much longer cell arrays.
You can use struct or cell2struct to create the structure.
headers_ca = {'time','x','y'};
headers_ca(2, :) = {ival};
s = struct(headers_ca{:});
headers_ca = {'time','x','y'};
ivals = repmat({ival}, numel(headers_ca), 1);
s = cell2struct(ivals, headers_ca);
I'm trying to run a loop over different functions with different number of arguments. The variables are created at runtime inside the loop, and I want to use eval at each iteration to instantiate a Struct using the variable :symbol. However, I can't do this since eval only works in the global scope. This is the MWE for the case that works:
function f1(x); return x; end
function f2(x1,x2); return x1+x2; end
handles = [f1,f2]
args =[:(x1),:(x1,x2)]
x1 = 1; x2 = 1;
for (i,f) in enumerate(handles)
params = eval(args[i])
#show f(params...)
end
f(params...) = 1
f(params...) = 2
However, if I move the variable definitions inside the loop, which is what I actually want, it doesn't work after restarting Julia to clear the workspace.
function f1(x); return x; end
function f2(x1,x2); return x1+x2; end
handles = [f1,f2]
args =[:(x1),:(x1,x2)]
for (i,f) in enumerate(handles)
x1 = 1; x2 = 1;
params = eval(args[i])
#show f(params...)
end
ERROR: UndefVarError: x1 not defined
I've tried several of the answers, such as this one, but I can't seem to make it work. I could write a custom dispatch function that takes[x1,x2] and calls f1 or f2 with the correct arguments. But still, is there any way to do this with eval or with an alternative elegant solution?
EDIT: here are more details as to what I'm trying to do in my code. I have a config struct for each algorithm, and in this I want to define beforehand the arguments it takes
KMF_config = AlgConfig(
name = "KMF",
constructor = KMC.KMF,
parameters = :(mu,N,L,p),
fit = KMC.fit!)
MF_config = AlgConfig(
name = "MF",
constructor = KMC.MF,
parameters = :(mu,N,L),
fit = KMC.fit!)
alg_config_list = [KMF_config, MF_config]
for (i,alg_config) in enumerate(alg_config_list)
mu,N,L,p,A,B,C,D,data = gen_vars() #this returns a bunch of variables that are used in different algorithms
method = alg_config.constructor(eval(method.parameters)...)
method.fit(data)
end
One possible solution is to have a function take all the variables and method, and return a tuple with a subset of variables according to method.name. But I'm not sure if it's the best way to do it.
Here's an approach using multiple dispatch rather than eval:
run_a(x, y) = x + 10*y
run_b(x, y, z) = x + 10*y + 100*z
extract(p, ::typeof(run_a)) = (p.x, p.y)
extract(p, ::typeof(run_b)) = (p.x, p.y, p.z)
genvars() = (x=1, y=2, z=3)
function doall()
todo = [
run_a,
run_b,
]
for runalg in todo
v = genvars()
p = extract(v, runalg)
#show runalg(p...)
end
end
In your example you would replace run_a and run_b with KMC.KMF and KMC.MF.
Edit: Cleaned up example to avoid structs that don't exist in your example.
I am stuck at creating a matrix of a matrix (vector in this case)
What I have so far
index = zeros(size(A)) // This is some matrix but isn't important to the question
indexIndex = 1;
for rows=1:length(R)
for columns=1:length(K)
if(A(rows,columns)==x)
V=[rows columns]; // I create a vector holding the row + column
index(indexIndex) = V(1,2) // I want to store all these vectors
indexIndex = indexIndex + 1
end
end
end
I have tried various ways of getting the information out of V (such as V(1:2)) but nothing seems to work correctly.
In other words, I'm trying to get an array of points.
Thanks in advance
I do not understand your question exactly. What is the size of A? What is x, K and R? But under some assumptions,
Using list
You could use a list
// Create some matrix A
A = zeros(8,8)
//initialize the list
index = list();
// Get the dimensions of A
rows = size(A,1);
cols = size(A,2);
x = 0;
for row=1:rows
for col=1:cols
if(A(row,col)==x)
// Create a vector holding row and col
V=[row col];
// Append it to list using $ (last index) + 1
index($+1) = V
end
end
end
Single indexed matrices
Another approach would be to make use of the fact an multi-dimensional matrix can also be indexed by a single value.
For instance create a random matrix named a:
-->a = rand(3,3)
a =
0.6212882 0.5211472 0.0881335
0.3454984 0.2870401 0.4498763
0.7064868 0.6502795 0.7227253
Access the first value:
-->a(1)
ans =
0.6212882
-->a(1,1)
ans =
0.6212882
Access the second value:
-->a(2)
ans =
0.3454984
-->a(2,1)
ans =
0.3454984
So that proves how the single indexing works. Now to apply it to your problem and knocking out a for-loop.
// Create some matrix A
A = zeros(8,8)
//initialize the array of indices
index = [];
// Get the dimensions of A
rows = size(A,1);
cols = size(A,2);
x = 0;
for i=1:length(A)
if(A(i)==x)
// Append it to list using $ (last index) + 1
index($+1) = i;
end
end
Without for-loop
If you just need the values that adhere to a certain condition you could also do something like this
values = A(A==x);
Be carefull when comparing doubles, these are not always (un)equal when you expect.
I am having trouble figuring out how to get the length of a matrix within a matrix within a matrix (nested depth of 3). So what the code is doing in short is... looks to see if the publisher is already in the array, then it either adds a new column in the array with a new publisher and the corresponding system, or adds the new system to the existing array publisher
output[k][1] is the publisher array
output[k][2][l] is the system
where the first [] is the amount of different publishers
and the second [] is the amount of different systems within the same publisher
So how would I find out what the length of the third deep array is?
function reviewPubCount()
local output = {}
local k = 0
for i = 1, #keys do
if string.find(tostring(keys[i]), '_') then
key = Split(tostring(keys[i]), '_')
for j = 1, #reviewer_code do
if key[1] == reviewer_code[j] and key[1] ~= '' then
k = k + 1
output[k] = {}
-- output[k] = reviewer_code[j]
for l = 1, k do
if output[l][1] == reviewer_code[j] then
ltable = output[l][2]
temp = table.getn(ltable)
output[l][2][temp+1] = key[2]
else
output[k][1] = reviewer_code[j]
output[k][2][1] = key[2]
end
end
end
end
end
end
return output
end
The code has been fixed here for future reference: http://codepad.org/3di3BOD2#output
You should be able to replace table.getn(t) with #t (it's deprecated in Lua 5.1 and removed in Lua 5.2); instead of this:
ltable = output[l][2]
temp = table.getn(ltable)
output[l][2][temp+1] = key[2]
try this:
output[l][2][#output[l][2]+1] = key[2]
or this:
table.insert(output[l][2], key[2])