assign wfwe = wb_acc & (adr_i == 2'b10) & ack_o & we_i;
For the above assign statement which is in verilog, i getting error while implememting it in z3
My code:
BitVecExpr[] wfwe = new BitVecExpr[1];
BitVecExpr[] wb_acc = new BitVecExpr[1];
BitVecExpr[] adr_i = new BitVecExpr[1];
BitVecExpr[] ack_o = new BitVecExpr[1];
BitVecExpr[] we_i = new BitVecExpr[1];
wfwe[0] = ctx.mkBVConst("wfwe",1);
wb_acc[0] = ctx.mkBVConst("wb_acc",1);
adr_i[0] = ctx.mkBVConst("adr_i",2);
ack_o[0] = ctx.mkBVConst("ack_o",1);
we_i[0] = ctx.mkBVConst("we_i",1);
Solver s = ctx.mkSolver();
s.add(ctx.mkBVAND(wb_acc[0],ctx.mkEq(adr_i[0],ctx.mkNumeral("2",2)),ack_o[0],we_i[0]));
I am getting error in above add statement:
error: method mkBVAND in class Context cannot be applied to given types;
required: BitVecExpr,BitVecExpr
found: BitVecExpr,BoolExpr
Which is true. Can anyone suggest me workaround. Am i implementing it incorrectly please let me know.
This error is reported because the second argument of mkBVAND is a Boolean expression (ctx.mkEq ...). Note that Booleans and BitVectors of size 1 are not the same thing, and they will not be converted automatically. The easiest way to convert between them is an if-then-else the selects the right values.
These are the problems with this example:
1) ctx.mkNumeral("2",2) is incorrect. I guess the intention was to create a bv-numeral of 2 bits with value 2; the easiest way to achieve that is ctx.mkBV(2, 2)
2) The 2nd argument of mkBVAND needs to be converted from Bool to BitVector, e.g., like so:
BoolExpr c = ctx.mkEq(adr_i[0], ctx.mkBV(2, 2));
BitVecExpr e = (BitVecExpr) ctx.mkITE(c, ctx.mkBV(1, 1), ctx.mkBV(0, 1));
e being the result.
3) ctx.mkBVAND takes exactly 2 arguments, no more and no less. Thus, the BVAND expression needs to be rewritten, e.g., like so:
ctx.mkBVAND(ctx.mkBVAND(wb_acc[0], e), ctx.mkBVAND(ack_o[0], we_i[0])))
4) The result needs to be converted to a Boolean expression again, e.g.
ctx.mkEq(q, ctx.mkBV(1, 1))
where q is the result of the BVAND.
Related
I store various formulas in Postgres and I want to use those formulas in my code. It would look something like this:
var amount = 100;
var formula = '5/105'; // normally something I would fetch from Postgres
var total = amount * formula; // should return 4.76
Is there a way to evaluate the string in this manner?
As far as I'm aware, there isn't a formula solver package developed for Dart yet. (If one exists or gets created after this post, we can edit it into the answer.)
EDIT: Mattia in the comments points out the math_expressions package, which looks pretty robust and easy to use.
There is a way to execute arbitrary Dart code as a string, but it has several problems. A] It's very roundabout and convoluted; B] it becomes a massive security issue; and C] it only works if the Dart is compiled in JIT mode (so in Flutter this means it will only work in debug builds, not release builds).
So the answer is that unfortunately, you will have to implement it yourself. The good news is that, for simple 4-function arithmetic, this is pretty straight-forward, and you can follow a tutorial on writing a calculator app like this one to see how it's done.
Of course, if all your formulas only contain two terms with an operator between them like in your example snippet, it becomes even easier. You can do the whole thing in just a few lines of code:
void main() {
final amount = 100;
final formula = '5/105';
final pattern = RegExp(r'(\d+)([\/+*-])(\d+)');
final match = pattern.firstMatch(formula);
final value = process(num.parse(match[1]), match[2], num.parse(match[3]));
final total = amount * value;
print(total); // Prints: 4.761904761904762
}
num process(num a, String operator, num b) {
switch (operator) {
case '+': return a + b;
case '-': return a - b;
case '*': return a * b;
case '/': return a / b;
}
throw ArgumentError(operator);
}
There are a few packages that can be used to accomplish this:
pub.dev/packages/function_tree
pub.dev/packages/math_expressions
pub.dev/packages/expressions
I used function_tree as follows:
double amount = 100.55;
String formula = '5/105*.5'; // From Postgres
final tax = amount * formula.interpret();
I haven't tried it, but using math_expressions it should look like this:
double amount = 100.55;
String formula = '5/105*.5'; // From Postgres
Parser p = Parser();
// Context is used to evaluate variables, can be empty in this case.
ContextModel cm = ContextModel();
Expression exp = p.parse(formula) * p.parse(amount.toString());
// or..
//Expression exp = p.parse(formula) * Number(amount);
double result = exp.evaluate(EvaluationType.REAL, cm);
// Result: 2.394047619047619
print('Result: ${result}');
Thanks to fkleon for the math_expressions help.
Via an enterpreise service consumer I connect to a webservice, which returns me some data, and also url's.
However, I tried all methods of the mentioned class above and NO METHOD seems to convert the unicode-characters inside my url into the proper readable characters.... ( in this case '=' and ';' ) ...
The only method, which runs properly is "is_valid_url", which returns false, when I pass url's like this:
http://not_publish-workflow-dev.hq.not_publish.com/lc/content/forms/af/not_publish/request-datson-internal/v01/request-datson-internal.html?taskId\u003d105862\u0026wcmmode\u003ddisabled
What am I missing?
It seems that this format is for json values. Usually = and & don't need to be written with the \u prefix. To decode all \u characters, you may use this code:
DATA(json_value) = `http://not_publish-workflow-dev.hq.not_publish.com/lc`
&& `/content/forms/af/not_publish/request-datson-internal/v01`
&& `/request-datson-internal.html?taskId\u003d105862\u0026wcmmode\u003ddisabled`.
FIND ALL OCCURRENCES OF REGEX '\\u....' IN json_value RESULTS DATA(matches).
SORT matches BY offset DESCENDING.
LOOP AT matches ASSIGNING FIELD-SYMBOL(<match>).
DATA hex2 TYPE x LENGTH 2.
hex2 = to_upper( substring( val = json_value+<match>-offset(<match>-length) off = 2 ) ).
DATA(uchar) = cl_abap_conv_in_ce=>uccp( hex2 ).
REPLACE SECTION OFFSET <match>-offset LENGTH <match>-length OF json_value WITH uchar.
ENDLOOP.
ASSERT json_value = `http://not_publish-workflow-dev.hq.not_publish.com/lc`
&& `/content/forms/af/not_publish/request-datson-internal/v01`
&& `/request-datson-internal.html?taskId=105862&wcmmode=disabled`.
I hate to answer my own questions, but anyway, I found an own solution, via manually replacing those unicodes. It is similar to Sandra's idea, but able to convert ANY unicode.
I share it here, just in case, any person might also need it.
DATA: lt_res_tab TYPE match_result_tab.
DATA(valid_url) = url.
FIND ALL OCCURRENCES OF REGEX '\\u.{4}' IN valid_url RESULTS lt_res_tab.
WHILE lines( lt_res_tab ) > 0.
DATA(match) = substring( val = valid_url off = lt_res_tab[ 1 ]-offset len = lt_res_tab[ 1 ]-length ).
DATA(hex_unicode) = to_upper( match+2 ).
DATA(char) = cl_abap_conv_in_ce=>uccp( uccp = hex_unicode ).
valid_url = replace( val = valid_url off = lt_res_tab[ 1 ]-offset len = lt_res_tab[ 1 ]-length with = char ).
FIND ALL OCCURRENCES OF REGEX '\\u.{4}' IN valid_url RESULTS lt_res_tab.
ENDWHILE.
WRITE / url.
WRITE / valid_url.
I having an issue when trying to update a SF stateful service after updating a child object of the service state. The upgrade fails to pass the 1st upgrade domain with a 'package activation' error. Digging around in the event viewer on the offending node gives the below exception:
Errormsg=TStore.OnApplyAddAsync: Unexpected exception System.NullReferenceException: Object reference not set to an instance of an object.
at xxx.DataChildObject.GetHashCode(IEqualityComparer comp)
at xxx.Data.GetHashCode(IEqualityComparer comp)
at xxx.Data.GetHashCode() in C:\Users\xxx\Source\Repos\xxx\xxx\xxx.Core\Domain.fs:line 17
at System.Fabric.Store.TStore`5.OnApplyAdd(TransactionBase txn, MetadataOperationData metadataOperationData, RedoUndoOperationData operationRedoUndo, Boolean isIdempotent, String applyType) Assert=System.Exception: at System.Environment.GetStackTrace(Exception e, Boolean needFileInfo)
The change to the 'DataChildObject' was to add a new field that is a tuple of 2 doubles.
I understand that F# is automatically generating equality methods and these must be triggered during SF state and that due to datacontact serialisation these are null during the GetHashCode check.
I don't understand exactly when this check is being performed or why though?
As a test i tried overriding the GetHasCode method on my DataChildObject, but this didn't change the error i get when trying to upgrade my service.
[<DataContract>]
type DataChildObject =
class
[<DataMember(IsRequired=false,Name="Value1")>] val mutable Value1 : float * float
[<DataMember(IsRequired=false,Name="Value2")>] val mutable Value2 : float * float
[<DataMember(IsRequired=false,Name="NewValue")>] val mutable NewValue : float * float
new (v1,v2) = {Value1=v1;Value2=v2;NewValue=1.0,1.0}
override this.GetHashCode() =
let value1 = if (box this.Value1 = null) then 1 else this.Value1.GetHashCode()
let value2 = if (box this.Value2 = null) then 1 else this.Value2.GetHashCode()
let newValue = if (box this.NewValue = null) then 1 else (this.NewValue).GetHashCode()
value1+value2+newValue
end
I expect these domain objects to change more in the near future so any help in understanding exact how to get past or avoid this issue is helpful.
Thanks
i am new with f# , will be great if some 1 can help , nearly half a day gone solving this problem Thank you
module Certificate =
type T = {
Id: int
IsECert: bool
IsPrintCert: bool
CertifiedBy: string
Categories: Category.T list
}
let createPending now toZonedDateTime toBeCertifiedByName (job: Models.Job.T) (certificateType: Models.CertificateType.T) (pendingCertificate: Models.PendingCertificate.T) visualization (categories: Category.T list) =
let forCompletion = Models.PendingCertificate.getCertificateForCompletion pendingCertificate
{
Id = forCompletion.Id |> CertificateId.toInt
IsECert = Models.PendingCertificate.isECertificate pendingCertificate
IsPrintCert = Models.PendingCertificate.isPrintCertificate pendingCertificate
CertifiedBy = toBeCertifiedByName
Categories = categories}
i am getting an error in "Incomplete structured construct at or before this point"
Your formatting is all off. I will assume here that this is just a result of posting to StackOverflow, and your actual code is well indented.
The error comes from the definition of createPending: this function does not have a result. All its body consists of defining a forCompletion value, but there is nothing after it. Here's a simpler example that has the same problem:
let f x =
let y = 5
This function will produce the same error, because it also doesn't have a result. In F#, every function has to return something. The body cannot contain only definitions of helper functions or values. For example, I could fix my broken function above like this:
let f x =
let y = 5
x + y
This function first defines a helper value y, then adds it to its argument x, and returns the result.
> f 2
> 7
>
> f 0
> 5
How exactly you need to fix your function depends on what exactly you want it to mean. I can't help you here, because you haven't provided that information.
I am starting to learn Lua from Programming in Lua (2nd edition)
I didn't understand the following in the book. Its very vaguely explained.
a.) w={x=0,y=0,label="console"}
b.) x={math.sin(0),math.sin(1),math.sin(2)}
c.) w[1]="another field"
d.) x.f=w
e.) print (w["x"])
f.) print (w[1])
g.) print x.f[1]
When I do print(w[1]) after a.), why doesn't it print x=0
What does c.) do?
What is the difference between e.) and print (w.x)?
What is the role of b.) and g.)?
You have to realize that this:
t = {3, 4, "eggplant"}
is the same as this:
t = {}
t[1] = 3
t[2] = 4
t[3] = "eggplant"
And that this:
t = {x = 0, y = 2}
is the same as this:
t = {}
t["x"] = 0
t["y"] = 2
Or this:
t = {}
t.x = 0
t.y = 2
In Lua, tables are not just lists, they are associative arrays.
When you print w[1], then what really matters is line c.) In fact, w[1] is not defined at all until line c.).
There is no difference between e.) and print (w.x).
b.) creates a new table named x which is separate from w.
d.) places a reference to w inside of x. (NOTE: It does not actually make a copy of w, just a reference. If you've ever worked with pointers, it's similar.)
g.) Can be broken up in two parts. First we get x.f which is just another way to refer to w because of line d.). Then we look up the first element of that table, which is "another field" because of line c.)
There's another way of creating keys in in-line table declarations.
x = {["1st key has spaces!"] = 1}
The advantage here is that you can have keys with spaces and any extended ASCII character.
In fact, a key can be literally anything, even an instanced object.
function Example()
--example function
end
x = {[Example] = "A function."}
Any variable or value or data can go into the square brackets to work as a key. The same goes with the value.
Practically, this can replace features like the in keyword in python, as you can index the table by values to check if they are there.
Getting a value at an undefined part of the table will not cause an error. It will just give you nil. The same goes for using undefined variables.
local w = {
--[1] = "another field"; -- will be set this value
--["1"] = nil; -- not save to this place, different with some other language
x = 0;
y = 0;
label = "console";
}
local x = {
math.sin(0);
math.sin(1);
math.sin(2);
}
w[1] = "another field" --
x.f = w
print (w["x"])
-- because x.f = w
-- x.f and w point one talbe address
-- so value of (x.f)[1] and w[1] and x.f[1] is equal
print (w[1])
print ((x.f)[1])
print (x.f[1])
-- print (x.f)[1] this not follows lua syntax
-- only a function's has one param and type of is a string
-- you can use print "xxxx"
-- so you print x.f[1] will occuur error
-- in table you can use any lua internal type 's value to be a key
-- just like
local t_key = {v=123}
local f_key = function () print("f123") end
local t = {}
t[t_key] = 1
t[f_key] = 2
-- then t' key actualy like use t_key/f_key 's handle
-- when you user t[{}] = 123,
-- value 123 related to this no name table {} 's handle