Swift 3.1: Array too large to be initialized? (Program just freezes) - arrays

The Problem:
I have a semi-large [Int] array, which contains ~ 25K to 60K elements. It was originally outputted into a text file by my first program and needs to be fed as a let value into a second program. To do this, I manually copied it in. However, Swift just freezes whenever I try to initialize it. By freeze, I mean that it doesn't do anything, even after an hour.
Further investigation:
I confirmed that it was the size of the array causing the freeze-up, by creating a test program with just one line that just said let test = [the_array]. That program is still running after an hour.
I have previously used arrays that contained 400-450K elements without any problems. However, those arrays didn't have to be initialized as a variable/constant, and each element only contained a number between 1-9. The array that is causing the freeze-up definitely has less than 100K elements, but each element contains an integer between 100-300K.
How am I able to initialize the array into the second program, and what exactly is causing the problem?
Other info: I'm using Swift 3.1.1 on Ubuntu 16.04 64bit, so I don't have access to Xcode. If you need the text file of the array, please leave a comment.
File is uploaded here

I downloaded your file - a 600KB file is a very small size for any modern computer. This codes ran in under 1 second on my 2012 iMac:
let fileURL = URL(fileURLWithPath: "/path/to/file.txt")
let charset = CharacterSet.whitespacesAndNewlines.union(CharacterSet(charactersIn: "[]"))
let fileContent = try! String(contentsOf: fileURL).trimmingCharacters(in: charset)
let array = fileContent.components(separatedBy: ",").flatMap {
Int($0.trimmingCharacters(in: .whitespaces))
}
print(array.count) // 74061

Related

Error when trying to set array in userdefaults: Thread 1: "Attempt to insert non-property list object

I have solved the issue now, thanks for your help. I shouldn't have tried to save arrays with UITextViews, but I should have saved their text as strings instead. Here was the original question:
I have tried a lot, and googled a lot, but I can't solve this problem on my own. Whenever I try to save an array in userdefaults, it just is not working. I get the following error:
Thread 1: "Attempt to insert non-property list object (\n "<UITextView: 0x14001f800; frame = (0 0; 355 180); text = 'D'; clipsToBounds = YES; gestureRecognizers = <NSArray: 0x600003f01d10>; layer = <CALayer: 0x6000031c83e0>; contentOffset: {0, 0}; contentSize: {355, 30}; adjustedContentInset: {0, 0, 0, 0}>"\n) for key content"
I don't know what a non-property list object is. And I do not know how to solve the problem. Below is the lines of code that do not work.
var contentList: [Any] = []
let cl = defaults.array(forKey: "content")!
if cl.count != 0{
contentList += cl
}
contentList.append(label)
defaults.setValue(contentList, forKey: "content")
If I take out the last line of code by turning it into a comment everything runs just fine. How should I replace that line of code? I essentially want to save an array of UITextViews and make it larger every time I call a fucntion (this code is part of a larger function). The reason why I have created another two lists (cl and contentList) is that it helps me with a problem down the line. What I cannot understand however, is why the last line of code doesn't work. If anyone has any ideas, please help me, it would be much appreciated.
Use only String as stated in comments :
var contentList: [String] = []
let cl = defaults.array(forKey: "content")!
if cl.count != 0{
contentList += cl
}
If lbText = label.text {
contentList.append(lbText)
defaults.setValue(contentList, forKey: "content")
}
You can only store a very limited list of data types into UserDefaults, commonly referred to as "property list objects" (Since property list (or plist) files will only store the same data types.
To quote the Xcode docs on UserDefaults, in the section titled "Storing Default Objects":
A default object must be a property list—that is, an instance of (or for collections, a combination of instances of) NSData, NSString, NSNumber, NSDate, NSArray, or NSDictionary [or Data, String, NSNumber, Date, Array, or Dictionary types in Swift.] If you want to store any other type of object, you should typically archive it to create an instance of Data.
(I added the equivalent Swift types to the above quote in square brackets, since it looks like Apple hasn't updated it for Swift.)
That's worded a little awkwardly. The idea is that you can only store data of the types listed. Because the Array and Dictionary types are "container" types, you can store any combination of arrays and dictionaries that contain combinations of any of the above types. For example, you can store an array that contains a dictionary, 3 dates, 2 floats, a Double, some Data, and 2 arrays, and those dictionaries and arrays can contain other dictionaries and/or arrays.)
It is almost always wrong to archive UIView objects like UITextViews. You should save the text properties of your text views instead.
If you want to manage a vertical stack of UITextView objects, I suggest adding a vertical stack view to your user interface, and then writing code that adds or removes UITextView subviews to your stack view. You should be able to find plenty of examples of adding and removing objects from stack views online. (It's really easy.)
If you want to manage a scrolling list of feeds of arbitrary length, you might want to use a table view or collection view instead. Those require that you set up a data model and implement a "data source". That takes a little practice to get right, but is very powerful.

How to convert a large number of 2D arrays (over 200k arrays) to 1D arrays in Google Apps Script?

I want to convert a large number of 2D arrays (over 200k arrays) to 1D arrays with Google Apps Script. When the number of 2D data arrays is 120,000, the following codes are working well without any problem . But they didn’t work when the number of arrays was 130,000. Looks like some limitation in .concat method. In my actual application, the error message returned "RangeError: Maximum call stack size exceeded". Can anyone help? Or is there a better method to get 1D array data directly from one column data in Google Sheets? Thanks a lot for any recommendation!
function test() {
var write = [];
for (i = 0; i < 130000; ++i) {
write[i] = ['AAPL'];
}
SpreadsheetApp.getActiveSheet().getRange(1, 1, write.length, 1).setValues(write);
write = [];
//The code below converts 2D array data to 1D successfully when the number of data arrays is 120000.
var data = SpreadsheetApp.getActiveSheet().getRange('A1:A120000').getValues();
data = [].concat(...data);
console.log(data.length);
//The code below fails when the number of data arrays is 130000.
var data = SpreadsheetApp.getActiveSheet().getRange('A1:A130000').getValues();
data = [].concat(...data);
}
.FLAT()
.getRange('A1:A120000').getValues().flat();
Here is some reference.
An IDE like visual studio code will know this as an array option. The online script editor does not give this as an option in autocomplete but it will works. Because the online IDE does not has this option inside his auto intelligence the editor will not know you working with arrays moving forward.

Locating a dynamic string in a text file

Problem:
Hello, I have been struggling recently in my programming endeavours. I have managed to receive the output below from Google Speech to Text, but I cannot figure out how draw data from this block.
Excerpt 1:
[VoiceMain]: Successfully initialized
{"result":[]}
{"result":[{"alternative":[{"transcript":"hello","confidence":0.46152416},{"transcript":"how low"},{"transcript":"how lo"},{"transcript":"how long"},{"transcript":"Polo"}],"final":true}],"result_index":0}
[VoiceMain]: Successfully initialized
{"result":[]}
{"result":[{"alternative":[{"transcript":"hello"},{"transcript":"how long"},{"transcript":"how low"},{"transcript":"howlong"}],"final":true}],"result_index":0}
Objective:
My goal is to extract the string "hello" (without the quotation marks) from the first transcript of each block and set it equal to a variable. The problem arises when I do not know what the phrase will be. Instead of "hello", the phrase may be a string of any length. Even if it is a different string, I would still like to set it to the same variable to which the phrase "hello" would have been set to.
Furthermore, I would like to extract the number after the word "confidence". In this case, it is 0.46152416. Data type does not matter for the confidence variable. The confidence variable appears to be more difficult to extract from the blocks because it may or may not be present. If it is not present, it must be ignored. If it is present however, it must be detected and stored as a variable.
Also please note that this text block is stored within a file named "CurlOutput.txt".
All help or advice related to solving this problem is greatly appreciated.
You could do this with regex, but then I am assuming you will want to use this as a dict later in your code. So here is a python approach to building this result as a dictionary.
import json
with open('CurlOutput.txt') as f:
lines = f.read().splitlines()
flag = '{"result":[]} '
for line in lines: # Loop through each lin in file
if flag in line: # check if this is a line with data on it
results = json.loads(line.replace(flag, ''))['result'] # Load data as a dict
# If you just want to change first index of alternative
# results[0]['alternative'][0]['transcript'] = 'myNewString'
# If you want to check all alternative for confidence and transcript
for result in results[0]['alternative']: # Loop over each alternative
transcript = result['transcript']
confidence = None
if 'confidence' in result:
confidence = result['confidence']
# now do whatever you want with confidence and transcript.

Select random item from an array with certain probabilities and add it to the stage

Its quite a big task but ill try to explain.
I have an array with a list of 200 strings and I want to be able to randomly select one and add it to the stage using code. I have movieclips exported for actionscript with the same class name as the strings in the array. Also, if it is possible, would I be able to select the strings with predictability such as the first has a 0.7 chance the second a 0.1 etc. Here is what i have currently
var nameList:Array=["Jimmy","Bob","Fred"]
var instance:DisplayObject = createRandom(nameList);
addChild(instance);
function createRandom(typeArray:Array):*
{
// Select random String from typeArray.
var selection:String = typeArray[ int(Math.random() * typeArray.length) ];
// Create instance of relevant class.
var Type:Class = getDefinitionByName(selection) as Class;
// Return created instance.
return new Type();
}
All this throws me this error
ReferenceError: Error #1065: Variable [class Jimmy] is not defined.
Ive searched for other threads similar but none combine the three specific tasks of randomisation, predictability and addChild().
I think that you've got two problems: a language problem and a logic problem. In the .fla connected to your code above, in the Library find each symbol representing a name and write into the 'AS linkage' column for that symbol the associated name -- e.g., 'Bob,' 'Fred' -- just the name, no punctuation.
Now getDefinitionByName() will find your 'Class'
If you put a different graphic into each MovieClip -- say, a piece of fruit or a picture of Bob,Jim, Fred -- and run your program you'll get a random something on stage each time.
That should solve your language problem. But the logic problem is a little harder, no?
That's why I pointed you to Mr. Kelly's solution (the first one, which for me is easier to grasp).

Hash-based logger for embedded application

Currently I am sending the UART the strings I want to log and reading it on the host with any terminal.
In order to reduce the logging time and hopefully the image size as well (my flash is tiny), I figured out that the strings are unused in the embedded system, so why storing them on the flash?
I want to implement a server, whom I can send a hashed-key of any string (for example - it's ROM address) and the string will be output to file or screen.
My questions are:
How to create the key2string converter out of the image file (the OS is CMX, but can be answered generally)
Is there a recomended way to generate image, that will know the strings addresses but will exclude them from ROM?
Is there a known generic (open-source or other) that implemented a similar logger?
Thanks
Rather than holding hard-coded strings, then trying to hash the answers and sent it via a UART, then somehow remove the strings from the resulting image, I suggest the following.
Just send an index for an error code. The PC side can look up that index and determine what the string is for that condition. If you want the device code to be more clear, the index can be an enumeration.
For example:
enum errorStrings
{
ES_valueOutOfLimits = 1,
ES_wowItsGettingWarm = 2,
ES_randomError = 3,
ES_passwordFailure = 4
};
So, if you were sending data to the UART via printf, you could do the following:
printf("%d\n",(int)ES_wowItsGettingWarm);
Then your PC software just needs to decode the "2" that comes across the UART back into a useful string of "Wow it's getting warm."
This keeps the firmware small, but you need to manually keep the file containing the enum and the file with the strings in sync.
My solution is sending file name and line (which should be 14-20 Byte) and having a source parser on the server side, which will generate map of the actual texts. This way the actual code will contain no "format" strings, but single "filename" string for each file. Furthermore, file names can be easily replaced with enum (unlike replacing every string in the code) to reduce the COMM throughput.
I hope the sample psaudo-code will help clarifying the idea:
/* target code */
#define PRINT(format,...) send(__FILE__,__LINE__,__VA_ARGS__)
...
/* host code (c++) */
void PrintComm(istream& in)
{
string fileName;
int line,nParams;
int* params;
in>>fileName>>line>>nParams;
if (nParams>0)
{
params = new int[nParams];
for (int i=0; i<nParams; ++i)
in>>params[i];
}
const char* format = FindFormat(fileName,line);
...
delete[] params;
}

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