I have been trying to access the values of the the array .. in the foreach loop but no luck, the first two calls get the values, but the ones in the foreach loop nothing.. comes empty although if i print the array all the values are there.
You never actually access the $dish variable in the foreach loop.
Try
$dish['Dish']['dish_name'];
instead of
$dishes['Dish']['dish_name'];
etc.
Additionally, you will get an error because the first element in your array is not a Dish, its a Dish_Category. Thus, either remove this element from the array, or use a simple if statement before you access the $dish such as:
if($dish['dish_name'])
//DO STUFF HERE
Also, there is no reason for so many
<?php ?>
tags. Couldn't you put the whole block of code in one?
Related
I am currently having trouble filling up an array of customClass.
I try to fill it with a jsonFile. During my json parsing (using swiftyJSON) i loop and fill my array.
The problem is, at the end of my loop, it is still empty. I tested it in different ways, and here is my code:
That's the file where the problem is. In my loop I fill an Annotation, that I add with append to my array. The problem is what my print return. Here is a part of it:
It's just a small part of a huge jsonfile. And, my tmpAnnot.name is correctly printed every iteration. But when it comes to my Array, nothing.
So I'm completly lost and hope you could help me ^^
(And for the information, here is my custom class) :
And btw, I tried to print my array.count, and it's nil too
Im so sorry if the question has been posted. I couldn't find it in the entire website.
Change your JSONAnnotationList declaration to be an non-optional and assign it an empty array
var JSONAnnotationList: [UGOAnnotation] = []
You see, you have never created an array so there was nothing to be printed.
The whole point of optionals is to use them sparingly, not everywhere.
hash_test.pl
#a=("f","a","b");
$K{"f"}{"aa"}=1;
$K{"a"}{"aa"}=1;
$k{"b"}{"bb"}=1;
foreach(#a){
#c= sort keys %{$k{$_}};
}
print "#c\n";
foreach(#c) {...}
perl hash_test.pl
bb
I want to keep the keys of the hash into an array, so that I can use the array as an input for the following statements.
But it seemed that the assay #c just only hold the last element.
Could anyone tell me why or help me to improve the script?
You assign the array every time in the foreach, thus overwriting it every time. So you end up with only having the last thing assigned to it. If you move the print inside the foreach you'll see that they are all there.
To store those keys you need to add them to the array, not assign the array. I've corrected the typo $k to $K, and changed aa that goes with f to ff (expecting it to be a typo as well).
my #c;
foreach my $el (#a) {
push #c, sort keys %{$K{$el}};
}
print "#c\n";
This prints the line: ff aa bb. Every time through the loop all keys found in the hash for a particular array element are added to #c, each as a separate element. So #c will contain all bottom-level keys across the whole data structure.
However, there is more that I would like to suggest.
Always use strict; and use warnings; This is not pedantry but it directly helps. I never write code without them. The typo would be caught here, for example.
Use descriptive variable names. Specifically, single-letter variable names are just too easy to confuse, unless in very short loops or where it is crystal clear what they are. (For example, a typo like this couldn't really happen.) Most importantly, the code is going to be far nicer to work with. That generally results in better code.
Please use good indentation and spacing. It helps a lot, in many ways.
A useful core package for nested data structures is Data::Dumper, which can print the whole thing nicely formatted so we can see it. Try to add to the end of your code
use Data::Dumper;
print Dumper(\%K);
There are yet others that do the same or similar.
Here is another way to do what you ask.
my #lowest_keys = map { sort keys %{$K{$_}} } #a;
I call them lowest_keys to emphasize that these are the ones from the last hash in your data structure, the bottom of it. The map applies processing in the block { ... } to each element of #a in turn, returning a list with all these results. (If any one result itself is a list, with more elements than one, it gets merged into the overall output list. So this may create the output list with many more elements than the input.) This list can then be assigned to an array, as above, or passed on to another function that expects a list as input, or interated over.
The map is generally used to transform an array into another, by doing to each element what is in { ... } block. Its close cousin grep is used to filter, so passing through only the elements of the input list for which the condition in { ... } evaluates to true, forming the output list. For example, filter out undefined array elements: my #good = grep { defined } #all
Variable names are case sensitive, so %K... and %k... are not the same.
Always use
use strict;
use warnings;
and declare your variables with my. That prevents you from making this kind of mistakes.
I had got a script in Perl and my task is to do some changes in it. This of course means to understand which part does exactly what. I am not familiar with Perl language but I tried to read through some tutorials, but still some things are confusing me. And I got stuck in following part:
while (<KOEFICIENTYfile>) {
#_=(split(/\s+/, $_));
push(#ZAID,shift(#_));
$KOEFICIENTY{$ZAID[-1]}=[#_];
}
As I understands this part then it:
Reads line from filehandle KOEFICIENTYfile
Separates them by spaces (one or more)
Loads first item from this separated array into array ZAID (and in the process, removes it from #_)
??? Adds a rest of a separated array into array KOEFICIENTY? I am confused by curly brackets part and by square brackets after equals sign.
I think that I understood the meaning of #, $, #_ or negative indexing but this is beyond me. Can you please advice me on meaning of this?
[-1] indexing is just a shortcut way to say "last element of the array".
KOEFICIENTY is actually a hash (you can tell this because it is using curly braces, instead of square ones, around the index), so you're putting the rest of the array #_ into a hash called KOEFICIENTY with a key of the last element of the array.
If you include:
use Data::Dumper
at the top of the script and do
print Dumper(%KOEFICIENTY)
it will nicely format the output for you, which may help
The original coder was trying to be too clever using the negative offset. It would have been much more obvious if the code had been written with a simple temporary variable thus:
while (<KOEFICIENTYfile>) {
#_ = (split(/\s+/, $_));
my $key = shift(#_);
push(#ZAID, $key);
$KOEFICIENTY{$key} = [#_];
}
The braces on $KOEFICIENTY show that this is a "hash" of key/value pairs named %KOEFICIENTY, and not a normal array.
If you don't actually need to preserve the sort order of the keys you could just use keys %KOEFICIENTY to retrieve them instead of storing them in #ZAID.
#zaid is a list, into which the first part of the split is added.
%KOEFICIENTY is a hash, in which a reference to the rest of the split is stored as a list reference under the key of the first part.
So if the line is a b c, #zaid will get a and %KOEFICIENTY{'a'} will hold a reference to a list containing b and c.
I'm using an analog of Shopify and I'm stuck with syntax of Liquid.
I need to output in the template the field with an id product[product_field_values_attributes][][value]
So I need to write a loop to get the i value of this array.
I'm confused with this empty element in the brackets.
I've looked through the examples of loop syntax in Liquid but all of those arrays are simple and they are not my case.
For example, the Title field has id product[title] and in Liquid template i call this variable product.title and it works fine.
But all my tries to write a loop for this array failed.
Please, help to write a loop to get the values of the array stated above.
Try outputting the array directly onto the page using {{ product }} or {{ product[product_field_values_attributes] }} somewhere in the HTML. That will do a JSON-like string representation of the array. From there you can figure out what the keys for the array are.
I'm not sure what you're saying about the i value. You don't reference i anywhere else in your question. If you can clarify that then we can see if something can be done about it.
There is an array of objects. I'm trying to removeChild an object from that array like below. removeChild works fine but the array won't refresh itself after removing uppest object. As you can see in below, i tried to trace array items out.
Firstly, array has three items, obviously the myArray.length must be 3.
After removing a child, myArray.length must be 2, but it get 3 (Wrong).
removeChild(myArray[currShape]);
trace(myArray);
Please tell me what am i missing here.
Assuming you're using ActionScript, removeChild() only serves to take objects off the stage. It doesn't take things out of an array. You have to take the object out of the array manually in another statement.
You could try something like:
removeChild(myArray.splice(currShape,1));
This removes the entry from the array and returns that entry that will be used to remove it from the stage.