2022-06-30

Java Map

Map map = new HashMap<>();

IntStream.range(0,4).forEach(i->map.put("str"+i,i));

System.out.println(map);

///////////////////////////////////////////

List<Map.Entry<String, Integer>> list = map.entrySet().stream()

.sorted(Map.Entry.comparingByValue(Comparator.reverseOrder()))

.sorted((a,b)->b.getValue()-a.getValue())

.limit(3).collect(Collectors.toList());

System.out.printf("\nList:%s:%d", list.get(0).getKey(), list.get(0).getValue());

list.forEach(entry -> System.out.printf("\n%s:%d", entry.getKey(), entry.getValue()));

Optional<Map.Entry<String, Integer>> opt = map.entrySet().stream()

.sorted(Map.Entry.comparingByValue(Comparator.reverseOrder()))

.limit(3).findFirst();

System.out.printf("\nOpt:%s:%d", opt.get().getKey(), opt.get().getValue());

Map<String, Integer> map2 = map.entrySet().stream()

.sorted((a,b)->b.getValue()-a.getValue())

.limit(1).collect(Collectors.toMap(m->m.getKey(),m->m.getValue()));

System.out.println("map2:" + map2);

/////////////////////////////////////////////////////////////////////////////////////////////////////////////

map.forEach((k, v) -> System.out.println((k + ":" + v)));

map.entrySet().stream()
        .forEach(e -> System.out.println(e.getKey() + ":" + e.getValue()));

for (Map.Entry<String, Integer> entry : map.entrySet()) { System.out.println(entry.getKey() + ":" + entry.getValue()); }

for (String key : map.keySet()) { System.out.println(key + ":" + map.get(key)); }

for (Integer value : map.values()) { System.out.println(value); }

2022-06-16

Java ArrayDeque

ArrayDeque<Integer> q = new ArrayDeque<>();

IntStream.range(0, 5).forEach((i) -> {q.addFirst(i);});
System.out.println(q);

IntStream.range(0, 5).forEach((i) -> {
            System.out.printf("%d, ", q.pollFirst());
        }        );

System.out.println(q);

ArrayDeque<Integer> q = new ArrayDeque<>();

IntStream.range(0, 5).forEach((i) -> { q.addFirst(i); });

System.out.println(q);

//[4, 3, 2, 1, 0]

IntStream.range(0, 5).forEach((i) ->{System.out.printf("%d,",q.pollFirst());});

//4, 3, 2, 1, 0,

System.out.println(q); //[]

//q.clear();

###################################

2022-06-10

2022-06-09

Java Collections

https://www.programcreek.com/2014/04/check-if-array-contains-a-value-java/

1. Four Different Ways to Check If an Array Contains a Value

1) Using List:

public static boolean useList(String[] arr, String targetValue) {
	return Arrays.asList(arr).contains(targetValue);
}

2) Using Set:

public static boolean useSet(String[] arr, String targetValue) {
	Set<String> set = new HashSet<String>(Arrays.asList(arr));
	return set.contains(targetValue);
}

3) Using a simple loop:

public static boolean useLoop(String[] arr, String targetValue) {
	for(String s: arr){
		if(s.equals(targetValue))
			return true;
	}
	return false;
}

4) Using Arrays.binarySearch():
binarySearch() can ONLY be used on sorted arrays. If the array is sorted, you can use the following code to search the target element:

public static boolean useArraysBinarySearch(String[] arr, String targetValue) {	
	int a =  Arrays.binarySearch(arr, targetValue);
	if(a > 0)
		return true;
	else
		return false;
}

Comparator<Arrow> cmp = Comparator
        .comparing(Arrow::getWeight)
        .thenComparing(Arrow::getCount, Comparator.reverseOrder())
        .thenComparing((a, b) -> Character.compare(a.ch, b.ch));


listChar.sort(cmp);

 
List<Employee> sortedEmployees = employees.stream()
                .sorted(cmp).collect(Collectors.toList());

//////////////////////////////////////////////////////////////////////////////////////////////////////////

 Collections.sort(scores, new Comparator<Score>() {

        public int compare(Score o1, Score o2) {
            return o2.getScores().get(0).compareTo(o1.getScores().get(0));
        }
    });

Collections.sort(scores, (s1, s2) -> { return s1 - s2; });

Collections.binarySearch(cats, key);

String s = list.stream().map(Objects::toString)
.sorted(Comparator.reverseOrder()).collect(Collectors.joining(""));

int[] arr = {1,2,3};

var list = Arrays.stream(arr).boxed().toList();

list.subArray(int begin, int end)

2022-04-29

карпелянский владимир karpelansky

bfg591 rd16, rd100

https://www.youtube.com/watch?v=fb9FqkYN6kc

https://youtu.be/AJ2QLoGyUXE?t=153

filters

solidworks

красные кольца T25-2 до 14М, желтые T25-6 14М-60М, дальше бескорпусные

диапазонные фильтры https://youtu.be/lZK9xWR4PeI?t=447

диоды 4148 включают параллельно реле для погашения бросков самоиндукции

2022-04-12

TDA7052 amplifier | Low voltage 3V, 5V | 1 W

lm4871 hxj8002

https://www.youtube.com/watch?v=tVHfRD_mhWc

2022-04-05

Игонин, Igonin

https://www.youtube.com/watch?v=x4sK8aGVwyE

RDA1846

beken4815(19,18) bk4819

FD6818

Простейший АМ передатчик на средние волны. Проверка дальности. https://www.youtube.com/watch?v=ZRSLaGVer0A&t=603s

Простейший передатчик на 27 МГц. Проверка в полях.

https://www.youtube.com/watch?v=pWmJm5uctdI&t=150s

Увеличил мощность, проверяем дальность. Простейший передатчик на 27 МГц.

https://www.youtube.com/watch?v=t3LxkOdEbx0&t=82s

https://www.youtube.com/watch?v=IcAhviXtggM

https://www.youtube.com/watch?v=nn8hNtysaxw

https://www.youtube.com/watch?v=Xe7V6ZvPJGQ

3W beacon on Si5351 and arduino

https://www.youtube.com/watch?v=lf7M396e3cc с увч

https://www.youtube.com/watch?v=VZwTFN4zNk0

СВ передатчик - набор деталей с AliExpress. Средние Волны.

https://www.youtube.com/watch?v=CuUUSXX19Q8

https://www.youtube.com/watch?v=Q73dk375l-c

IRF510 https://youtu.be/lf7M396e3cc?t=74

2022-04-03

Goncharov

радиомикрофон https://www.youtube.com/watch?v=a03rA-KSqHc

3.7V 0.15Wt 1km

12V 1W

Измерительный генератор https://www.youtube.com/watch?v=AIjHHpM4E-I

Радиолюбительские антенны. Первая часть https://www.youtube.com/watch?v=rf9uywwX5uQ

П контур https://www.youtube.com/watch?v=vS47Au9owTE

Как настроить ДПФ

https://www.youtube.com/watch?v=T0Y4AYg_BhU

SDR 1000

https://www.youtube.com/watch?v=vYhLsiypC-U

https://radiobooka.ru/peredatchik/36-prostaya-karmannaya-radiostanciya-dlya-sela.html

ksv

Изготовление простейшего индикатора напряженности поля. Самодельный прибор для сравнения антенн https://www.youtube.com/watch?v=yx3270ZrMpg

kd521 4148 kd503

Как сделать простейший КСВ-Метр https://www.youtube.com/watch?v=HD3x8MvJQQo

https://www.youtube.com/watch?v=wWg8RNqFG8I

https://www.youtube.com/watch?v=I0gDxeYetkA

http://dl2kq.de/ant/3-21.htm

https://www.youtube.com/watch?v=-VszeNFqYhY

https://inventorkr.blogspot.com/2021/03/swr-meter.html#more

2022-04-01

transmitter

QN8027

SI4713

виктор гончаров https://www.youtube.com/watch?v=a03rA-KSqHc

игонин

https://www.youtube.com/watch?v=Xe7V6ZvPJGQ

https://www.youtube.com/watch?v=VZwTFN4zNk0&t=58s

Транзисторный передатчик 3 Мгц 5W 9-24V https://www.youtube.com/watch?v=yVBk_zQg-QI

https://www.youtube.com/watch?v=gyeNdjHt36A

Антенна Резинка,очень просто

https://www.youtube.com/watch?v=gnZp1yOjh2w

https://vi.aliexpress.com/item/1005004157294824.html?spm=a2g0o.productlist.main.113.18c17bffDUk9vd&algo_pvid=1ac5340d-fae4-4b23-bfc5-e051168c6f73&algo_exp_id=1ac5340d-fae4-4b23-bfc5-e051168c6f73-56&pdp_npi=4%40dis%21EUR%2118.30%2116.47%21%21%2119.19%21%21%402101f49816946968299997338e13bc%2112000028226102328%21sea%21SK%21139857366%21S&curPageLogUid=yItH8xZpHEue

https://inventorkr.blogspot.com/2020/06/5-watts-fm-rf-amplifier.html

https://inventorkr.blogspot.com/2021/10/how-to-make-simple-fm-transmitter.html

https://inventorkr.blogspot.com/2021/12/make-simple-fm-transmitter.html

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