I have the following nested struct:
hole 1x200 struct, diam 1x12 struct, which has the following fields: pos, freq1, fre12
That is:
hole(1 to 200).diam(1 to 12).pos
.freq1
.freq2
From a value (freq1 and freq2), I would like to obtain the field name of the struct. So I will need to find the value that matches with freq1 and freq2 and show the fieldname.
I tried to use structfun in order to apply a function to each field.
[struct.field]=structfun(#(x) find(x.freq1==27.059783995484867 & freq2==76.468355874897000))
But I guess I am writing something wrong on the code.
Also I create an anonymous fuction but I have the following error:
'Error using structfun / Inputs to STRUCTFUN must be scalar
structures'
. How ever when I verified if an specific value of the struct is scalar, I have a positive answerd: isscalar(hole(130).diam(10))
I belive I more near the solution using this script:
myfun=#(yourarray,desiredvalue) yourarray==desiredvalue;
%//Apply function to each field of scalar structure, it SCALAR??
desiredfieldindex=myfun(structfun(#(x) x,hole),26.697046257785030)
desiredFieldName=fNames(desiredFieldIndex)
I don´t know if I am in the rigth path, or I should utilize the function find. ALso I that case I don´t know how to implement it.
Couple of things.
FLOATING POINT VALUES! Careful!! Never compare a floating point value as val==0.3! do abs(val-0.3)<10^-8 or something similar. Read more here.
You are using structfun wrong. The function needs 2 arguments, and you are just passing 1! However, structfun will apply a function to each field so you are not using it rigth either in that sense. Lets see an example
example:
a.hithere=5;
a.notthis=3;
fun=#(x)x==5;
[isfive]=structfun(fun,a)
isfive =
1
0
As you can see, it applies the function to each of them. If you try to change the function to fun=#(x)x.hithere==5 you will get an error! As the function is applied to each field, and x.hithere.hithere or x.notthis.hithere do not exist.
If you want to check both values, you will need to check them independently making two separated calls to structfun or avoiding structfun and just making a for loop.
Related
For my simulation, I have a field that is called particle.current_theta. When this field is a single variable, I assign it a new value that is called just "theta" on my line 177. This theta has its value changed further down within my code, on lines 202 and 206. I want what I have printed in my terminal as tree_theta and current_theta to be very similar to each other but not quite identical (This part of the code basically detects whether or not my particle is entering or exiting a region). You can see all this in the image below:
Now, I need to make the field I have called particle.current_theta a [1x1] array, and assign the entry in my [1x1] array the "theta" value, as usual. However, simply making particle.current_theta a [1x1] array radically changes its value within the terminal and causes my simulation to break. You can see how the value for particle.theta (printed in terminal as "current theta") is now drastically different in the code below:
I suspect that making particle.currenttheta an array is making it mutate whenever theta is changed in some of those lines below. How do I prevent that from happening, and get results that are identical to using just a single variable. To be precise, I want particle.current_theta to save the numerical information that theta has at line 177 of code but not be changed afterwards. Because of the large size of my code now and the function calls within function calls, it would be infeasible for me to be able to create a mwe that replicates this issue. However, all help and advice is appreciated, and I will respond to and clarify any questions that people may have.
If theta is a scalar (and it appears to be), then it's unlikely that changing its value is what is changing particle.currenttheta. What is more likely is that you're passing the currenttheta to some function, and changing the value of the passed argument inside the function. Julia arrays are passed to functions "by reference", in the sense that a copy is not made, and instead any changes made inside the function change the original array. When you had currenttheta as a scalar (which are passed "by value" instead), when you pass that to a function, changes made inside the function do not affect the original currenttheta's value.
So if you're passing currenttheta to a function somewhere and don't want it to be modified inside the function, pass copy(particle.currenttheta) in that call instead.
If you're not doing that, or that doesn't solve the problem, we need more of the code to figure out where the change might actually be happening. If not the whole of it, at least the parts that handle currenttheta, and the parts that print it. (Also, it would massively help with clarity if you would use consistent names in the output. Sometimes it's treetheta and current theta, other times it's theta and particle.currentheta, and it's not clear where these are being printed from and what the difference - if any - is.)
I've been following the guide on Exceljet for how to create a recursive LAMBDA function that removes all numbers from a string. For example, A1B2C3D4E5 becomes ABCDE.
The only thing I wanted differently was to have the string containing the character omissions stored inside the function rather than the cell. So, I took away the chars parameter from the opening line and used the LET function to store the string.
The problem is I keep getting a #VALUE! error and can't work out why.
=LAMBDA(str,sub,
LET(chars,"0123456789",
IF(chars="",str,
ReplaceChars(
SUBSTITUTE(str,LEFT(chars),sub),
MID(chars,2,LEN(chars)-1),
sub
)
)
))
A nested LET() in a recursive LAMBDA() is going to be troublesome since every time you'd use the variable in the recursion you'd start from scratch. Replacing characters will therefor never stop (if my interpretation of this is correct). But in your case you don't even need to make a recursive LAMBDA() to replace numbers, for example:
=LAMBDA(str,LET(X,MID(str,SEQUENCE(LEN(str)),1),CONCAT(IF(ISNUMBER(X*1),"",X))))
Core of this function is now:
=LET(X,MID(A1,SEQUENCE(LEN(A1)),1),CONCAT(IF(ISNUMBER(X*1),"",X)))
which can be used outside of LAMBDA() just fine. We can even replace this with
=LET(X,MID(A1,SEQUENCE(LEN(A1)),1),CONCAT(IF(ISNUMBER(FIND(X,"0123456789")),"",X)))
to do the same thing with any character you want to replace.
Now you can call =REPLACECHARS(A1). However, IMHO the beauty of the use of variables is now lost and the original approach (for example here would have my personal preference.
So, I have tried to do the same in a case of array of structures where 'char name[100]' is the only data member.
1st part of the code
2nd part of the code
The problem that I have encountered here is that once I provide a no. of names during program runtime, the output screen either does not print anything afterwards, or, prints the data without sorting it.
output screen
I did not get any compile time errors so I believe that there is a flaw in the logic.
There's this another method I tried hoping to get positive results. I type-casted characters to integers hoping that ASCII values could be used to compare. But, the results are exactly the same (undesired results).
updated logic of the 2nd part of the code
I hope somebody helps me find a way to correct this logic or provide another logic that is efficient.
the sorting logic you used is good , but from what is see the use of function's in C need's to be provided by pointers. other wise all the data inside the function will born and die inside the function , and the all the variables in the Main will stay the same as given, that explains why the output is the same as the input
try to print inside the sorting function's to see if this is the problem.
Given:
abstract ABSGene
type NuGene <: Genetic.ABSGene
fqnn::ANN
dcqnn::ANN
score::Float32
end
function mutate_copy{T<:ABSGene}(gene::T)
all_fields_except_score = filter(x->x != :score, names(T))
all_fields_except_score = map(x->("mutate_copy(gene.$x)"),all_fields_except_score)
eval(parse("$(T)("*join(all_fields_except_score,",")*")"))
end
ng = NuGene()
mutated_ng = mutate_copy(ng)
results in:
ERROR: gene not defined
in mutate_copy at none:4
If I just look at it as a string (prior to running parse and eval) it looks fine:
"NuGene(mutate_copy(gene.fqnn),mutate_copy(gene.dcqnn))"
However, eval doesn't seem to know about gene that has been passed into the mutate_copy function.
How do I access the gene argument that's been passed into the mutate copy?
I tried this:
function mutate_copy{T<:ABSGene}(gene::T)
all_fields_except_score = filter(x->x != :score, names(T))
all_fields_except_score = map(x-> ("mutate_copy($gene.$x)"),all_fields_except_score)
eval(parse("$(T)("*join(all_fields_except_score,",")*")"))
end
But that expands the gene in the string which is not what I want.
Don't use eval! In almost all cases, unless you really know what you're doing, you shouldn't be using eval. And in this case, eval simply won't work because it operates in the global (or module) scope and doesn't have access to the variables local to the function (like the argument gene).
While the code you posted isn't quite enough for a minimal working example, I can take a few guesses as to what you want to do here.
Instead of map(x->("mutate_copy(gene.$x)"),all_fields_except_score), you can dynamically look up the field name:
map(x->mutate_copy(gene.(x)), all_fields_except_score)
This is a special syntax that may eventually be replaced by getfield(gene, x). Either one will work right now, though.
And then instead of eval(parse("$(T)("*join(all_fields_except_score,",")*")")), call T directly and "splat" the field values:
T(all_fields_except_score...)
I think the field order should be stable through all those transforms, but it looks a pretty fragile (you're depending on the score being the last field, and all constructors to have their arguments in the same order as their fields). It looks like you're trying to perform a deepcopy sort of operation, but leaving the score field uninitialized. You could alternatively use Base's deepcopy and then recursively set the scores to zero.
I need to assign data field (component of another field symbol) to field-symbol in a several places of code. For the sake of reusability I decided to encapsulate this code in procedure, but I cannot understand how to pass field-symbols into this procedure.
LOOP bseg ASSIGNING <bseg>
...
PERFORM assigning USING <bseg>
CHANGING <wrbtr>.
...
ENDLOOP.
FORM assigning USING <bseg> TYPE bseg
CHANGING <wrbtr> TYPE bseg-wrbtr
IF ...
some logic here
ASSIGN <bseg>-wrbtr TO <wrbtr>.
ELSE
ASSIGN <bseg>-skfbt TO <wrbtr>.
ENDIF.
ENDFORM.
This code does not work.
What should I do to change the field symbol reference too?
This is not possible, at least not the way you try to do it. Field symbols cannot be passed as the pointers they really are. If you need something like that, you'll have to use real references.
Not knowing anything about the rest of your code - it looks a bit weird. Why would you want to change data in BSEG fields directly? I can only assume that you're "abusing" fields to transport some custom value throughout the code, and that's usually a bad idea. And if you need to do this, I'd rather do it this way:
LOOP bseg ASSIGNING <bseg>.
IF foo.
l_my_wrbtr = <bseg>-wrbtr.
ELSE.
l_my_wrbtr = <bseg>-skfbt.
ENDIF.
" ... pro'lly thousands of lines I don't even want to see...
IF foo.
<bseg>-wrbtr = l_my_wrbtr.
ELSE.
<bseg>-skfbt = l_my_wrbtr.
ENDIF.
ENDLOOP.