QMap<QString,int> map;
QMap<int,QMap<QString,int>> table;
QMap<QString,int>::iterator iter = map.begin();
int i = 0;
while (iter != map.end())
{
if (condition) {
table.insert(i++,iter.key(),iter.value()); // <--- this is obviously wrong
else
++iter;
}
So bascially I need to filter our data in map and insert them as new QMap as a value in the table QMap.
How to go around with this?
Since Qt 5.1, when compiling as c++11, you could use an initializer list:
table.insert( i++, QMap<QString,int> {{iter.key(),iter.value()}} );
But the question title says "without instantiating", and that is not possible. This is just another constructor.
Related
Is there a way to populate a queue using elements from another random queue in a constraint-based way? For example,
class some_class;
rand bit [7:0] choices [$];
rand bit [7:0] chosen [$];
int num_choices = 20;
int num_chosen = 5;
function new();
endfunction
constraint choices_size_c { choices.size() == num_choices; }
constraint chosen_c {
chosen.size() == num_chosen;
foreach (chosen[i]) {
// check chosen[i] exists somewhere within choices
}
}
endclass
The idea is we have a number of valid choices that, for example, get programmed somewhere. Then we choose 5 of those valid choices for testing. Can this be done with constraints, or do I need to do this manually post-randomization?
Use the set membership operator inside
constraint chosen_c {
chosen.size() == num_chosen;
foreach (chosen[i]) {
chosen[i] inside {choices};
}
}
You can also add unique constraints to prevent repetition if that is a requirement you failed to mention
constraint uniq {
unique {choices};
unique {chosen};
}
I'm trying to implement a table valued function (as a SQLite virtual table).
It's a function that would take a string and return a table with all the words of the string.
If I call it with literal values like below, it works fine.
SELECT word FROM splitstring("abc def ghi")
If, however, I call it with a column from another table it doesn't work:
SELECT a.Name, word FROM article a, splitstring(a.Text)
The xBestIndex method gets called all right, but right after that, I get an exception from the ExecuteReader method. The exception message is "xBestIndex malfunction". The xFilter method does not get called because of the exception.
My xBestIndex implementation is simple, it just marks the parameter so I can see it in xFilter:
public override SQLiteErrorCode BestIndex(SQLiteVirtualTable table, SQLiteIndex index)
{
index.Outputs.ConstraintUsages.ElementAt(0).argvIndex = 1;
index.Outputs.ConstraintUsages.ElementAt(0).omit = 1;
return SQLiteErrorCode.Ok;
}
Am I'm doing something wrong or is it impossible to pass non-literal parameters to table valued functions?
Found the issue! I was using constraints that had usable=0. The BestIndex method gets called multiple times by SQLite, the second time with a non-usable constraint.
Here is the fixed body of the BestIndex method.
public override SQLiteErrorCode BestIndex(SQLiteVirtualTable table, SQLiteIndex index)
{
if (index.Inputs.Constraints.Count() != 2)
throw new ArgumentException("The generate_series function requires two integer (long) parameters!");
if (index.Inputs.Constraints.All(c=>c.usable == 1))
{
index.Outputs.ConstraintUsages.ElementAt(0).argvIndex = 1;
index.Outputs.ConstraintUsages.ElementAt(0).omit = 1;
index.Outputs.ConstraintUsages.ElementAt(1).argvIndex = 2;
index.Outputs.ConstraintUsages.ElementAt(1).omit = 1;
}
else
{
index.Outputs.IndexNumber = -1;
index.Outputs.EstimatedCost = double.MaxValue;
}
return SQLiteErrorCode.Ok;
}
Now I check the usable flag. When BestIndex gets called with a constraint with usable=0 I skip it i.e. return a high estimated cost for that index so it doesn't get used.
I'm relatively new to groovy and am using it in the context of a gradle build. So please don't be harsh if there is an easy out-of-the-box solution for this.
Basically I'm trying to accomplish the reverse of Return Nested Key in Groovy. That is, I have some keys read from the System.properties map for example user.home and corresponding values like C:\User\dpr. Now I want to create a map that reflects this structure to use it in a groovy.text.SimpleTemplateEngine as bindings:
[user : [home : 'C:\Users\dpr']]
The keys may define an arbitrary deep hierarchy. For example java.vm.specification.vendor=Oracle Corporation should become:
[java : [vm : [spec : [vendor : 'Oracle Corporation']]]]
Additionally there are properties with the same parents such as user.name=dpr and user.country=US:
[
user: [
name: 'dpr',
country: 'US'
]
]
Edit: While ConfigSlurper is really nice, it is somewhat too defensive with creating the nested maps as it stops nesting at the minimum depth of a certain key.
I currently ended up using this
def bindings = [:]
System.properties.sort().each {
def map = bindings
def split = it.key.split("\\.")
for (int i = 0; i < split.length; i++) {
def part = split[i];
// There is already a property value with the same parent
if (!(map instanceof Map)) {
println "Skipping property ${it.key}"
break;
}
if (!map.containsKey(part)) {
map[part] = [:]
}
if (i == split.length - 1) {
map[part] = it.value
} else {
map = map[part]
}
}
map = it.value
}
With this solution the properties file.encoding.pkg, java.vendor.url and java.vendor.url.bug are discarded, which is not nice but something I can cope with.
However the above code is not very groovyish.
You can use a ConfigSlurper :
def conf = new ConfigSlurper().parse(System.properties)
println conf.java.specification.version
If I have a list of items in an array that represent the names of modules:
var phaseNames:Array = new Array("directorsPrep", "checkIO", "pickupPhoto", "pickupPhoto", "syncing", "dailies", "pictureEdit", "soundEdit", "soundMix", "colorCorrection", "finishing");
and I want to go through each one of these and call a function within each instance of each module, how would I go about doing so. So far, I have the following:
private function changeStartViewDate(numDays:Number):void
{
startViewDate = rightDate(startViewDate.getMonth(), startViewDate.getDate() + numDays, startViewDate.getFullYear());
getDateInfo();
determineCalendarWeek();
var phaseNames:Array = new Array("directorsPrep", "checkIO", "pickupPhoto", "pickupPhoto", "syncing", "dailies", "pictureEdit", "soundEdit", "soundMix", "colorCorrection", "finishing");
for (var i:int = 0; i < wholeProject.length; i++)
{
wholeProject[i].moveProject(Number((1-2) * numDays));
}
for (i = 0; i < phaseNames.length; i++)
{
for (var j:int = 0; j < [phaseNames[i]].length; j++)
{
[phaseNames[i]].movePhase(Number((-1) * numDays));
}
}
}
But when I try to save it, I get the following error:
1084: Syntax Error: expecting identifier before dot.
It's telling me the error is on the following line:
[phaseNames[i]].movePhase(Number((-1) * numDays));
I tried doing something like the following, but it didn't work:
[phaseNames[i].movePhase(Number((-1) * numDays))];
The above attempt of trying to figure this out gave me the following error
1064: Invalid metadata.
Any help would be appreciated.
I am going to assume that:
Each value of your phaseNames array references an actual instance of some other class [and not the name of the class]
The instance defined in the phaseNames array is a child of the current class.
You should be able to do something like this:
var childName = phaseNames[0];
var myChild : myObjectType = this[childName];
// then call function
myChild.doStuff();
This approach is not dissimilar to what you have; I'm just doing it in more lines. I'm also adding the this keyword to access the child.
I bet if you tried this, directly, it would work:
this[phaseNames[i]].movePhase(Number((-1) * numDays));
I have to wonder why you haven't created an array of all the instances instead of an array of all the variables names that point to the instances.
im having some problems with jagged arrays stored in session for ASP.net i have some code which creates a jagged array, them populates, and then stores this populated jagged array into session
protected string[][] answersJArray;
answersJArray[0] = new string[4]("test","test1","test2","test3"};
answersJArray[1] = new string[4]("test","test1","test2","test3"};
Session.Add("answersJArray", answersJArray);
how would i loop through each jagged array in the session ?? if they were not in session i no i could do the following
for (j = 0; j < answersJArray[1].Length; j++)
{
label.Text = (answersJArray[1][j].ToString());
}
how would i do the above by looping through the session ??
thanks
First declare a jagged array variable and cast it from the session variable like so:
string[][] answersJArray = (string[][])Session["answersJArray"];
Then you can loop through the array like you were going to:
for (j = 0; j < answersJArray[1].Length; j++)
{
label.Text = (answersJArray[1][j].ToString());
}
Shouldn't be too tough. You can get the object out of session and cast it into a string[]. If it's a local variable, you can check its length and iterate that way. I might be misunderstanding your issue, but am I missing something by saying get the variable out of the Session map, so you can work with it as a strong-type?