Analysis of global temperature - Part 4

background-image: url(../img/fp-tower/website-background-white.svg)

class: center, middle

.title[.dark-green[Analysis of global temperature<br>Part 4]]

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-1a.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-1b.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-1c.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-1d.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-1e.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-1f.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-1g.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-1h.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-1i.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-2a.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-2b.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-2c.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-2d.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-2e.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-2f.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-2g.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-2h.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-2i.svg" style="width:900px;"/>

---
# foldMap in parallel

<img src="../img/foundation/parlist-foldMapPar-2j.svg" style="width:900px;"/>

---
# fold intermediate results in parallel

.center[<img src="../img/foundation/parlist-foldMapPar-3a.svg" style="width:450px;"/>]
---
# fold intermediate results in parallel

.center[<img src="../img/foundation/parlist-foldMapPar-3b.svg" style="width:450px;"/>]

---
# fold intermediate results in parallel

.center[<img src="../img/foundation/parlist-foldMapPar-3c.svg" style="width:450px;"/>]

---
# fold intermediate results in parallel

.center[<img src="../img/foundation/parlist-foldMapPar-3d.svg" style="width:450px;"/>]

---
# fold intermediate results sequentially

.center[<img src="../img/foundation/parlist-foldMapPar-4a.svg" style="width:300px;"/>]

---
# fold intermediate results sequentially

.center[<img src="../img/foundation/parlist-foldMapPar-4b.svg" style="width:300px;"/>]

---
# fold intermediate results sequentially

.center[<img src="../img/foundation/parlist-foldMapPar-4c.svg" style="width:300px;"/>]

---
# fold intermediate results sequentially

.center[<img src="../img/foundation/parlist-foldMapPar-4d.svg" style="width:300px;"/>]

---
# fold intermediate results sequentially

.center[<img src="../img/foundation/parlist-foldMapPar-4e.svg" style="width:300px;"/>]

---
# fold intermediate results sequentially

.center[<img src="../img/foundation/parlist-foldMapPar-4f.svg" style="width:300px;"/>]

---
# foldMap

.center[<img src="../img/foundation/parlist-foldLeft-6.svg" style="width:150px;"/>]

---
# Thread

```scala
def createThread(n: Int): Thread = new Thread {
  override def run(): Unit =
    println(s"Thread ${n}")
}

val threads = 1.to(4).map(createThread)
```

```scala
threads.foreach(_.start())
// Thread 1
// Thread 3
// Thread 2
// Thread 4
```

---
# Executor and Runnable

.fifty-seven-left[
```scala
import java.util.concurrent.Executors

val fixedPool = Executors.newFixedThreadPool(2)

def createRunnable(n: Int): Runnable =
  new Runnable {
    def run(): Unit =
      println(s"Runnable ${n}")
  }

val runnables = 1.to(4).map(createRunnable)
```

```scala
runnables.foreach(fixedPool.submit)
// Runnable 1
// Runnable 3
// Runnable 2
// Runnable 4
```
]

.thirty-seven-right[
<img src="../img/foundation/executor.svg" alt="Executor" style="width:400px;"/>
]

---
# Executor and Runnable

.fifty-seven-left[
```scala
import java.util.concurrent.Executors

val fixedPool = Executors.newFixedThreadPool(2)

def createRunnable(n: Int): Runnable =
  new Runnable {
    def run(): Unit = {
      val thread = Thread.currentThread
      println(s"[${thread.getName}] Runnable ${n}")
    }
  }

val runnables = 1.to(4).map(createRunnable)
```

```scala
runnables.foreach(fixedPool.submit)
// [pool-19-thread-1] Runnable 1
// [pool-19-thread-2] Runnable 3
// [pool-19-thread-1] Runnable 2
// [pool-19-thread-2] Runnable 4
```
]

.thirty-seven-right[
<img src="../img/foundation/executor.svg" alt="Executor" style="width:400px;"/>
]

---
# ExecutionContext and Future

```scala
import java.util.concurrent.Executors
import scala.concurrent.duration._
import scala.concurrent.{ Await, ExecutionContext, Future }

val fixedPool        = Executors.newFixedThreadPool(2)
val executionContext = ExecutionContext.fromExecutor(fixedPool)
```

```scala
val future = Future {
  Thread.sleep(1000)  // sleep 1 second
  1
}(executionContext)
// future: Future[Int] = Future(<not completed>)
```

---
# ExecutionContext and Future

```scala
import java.util.concurrent.Executors
import scala.concurrent.duration._
import scala.concurrent.{ Await, ExecutionContext, Future }

val fixedPool                 = Executors.newFixedThreadPool(2)
implicit val executionContext = ExecutionContext.fromExecutor(fixedPool)
```

```scala
val task = Future {
  Thread.sleep(1000)  // sleep 1 second
  3
}
// task: Future[Int] = Future(<not completed>)
```

--

```scala
Await.result(task, 2.minutes)
// res: Int = 3
```

---
# ExecutionContext and Future

```scala
import java.util.concurrent.Executors
import scala.concurrent.duration._
import scala.concurrent.{ Await, ExecutionContext, Future }

val fixedPool                 = Executors.newFixedThreadPool(2)
implicit val executionContext = ExecutionContext.fromExecutor(fixedPool)
```

```scala
val task = Future {
  Thread.sleep(1000 * 60 * 5)  // sleep 5 minutes
  3
}
// task: Future[Int] = Future(<not completed>)
```

```scala
Await.result(task, 2.minutes)
// java.util.concurrent.TimeoutException:
//   Future timed out after [2 minutes]
```

---
# ExecutionContext and Future

```scala
import java.util.concurrent.Executors
import scala.concurrent.duration._
import scala.concurrent.{ Await, ExecutionContext, Future }

val fixedPool                 = Executors.newFixedThreadPool(2)
implicit val executionContext = ExecutionContext.fromExecutor(fixedPool)
```

```scala
val task = Future {
  Thread.sleep(1000 * 60 * 5)  // sleep 5 minutes
  3
}
// task: Future[Int] = Future(<not completed>)
```

```scala
Await.result(task, Duration.Inf)
// res: Int = 3
```

---
# ExecutionContext and Future

.fifty-seven-left[
<br><br><br>
```scala
val future1   = Future { task(1) }
val future2   = Future { task(2) }

val response1 = Await.result(future1, Duration.Inf)
val response2 = Await.result(future2, Duration.Inf)
```
]

.thirty-seven-right[.center[
<img src="../img/foundation/future-parallel.svg" alt="Future sequential" style="width:300px;"/>
]]

---
# ExecutionContext and Future

.fifty-seven-left[
<br><br><br>
```scala
val future1   = Future { task(1) }
val response1 = Await.result(future1, Duration.Inf)

val future2   = Future { task(2) }
val response2 = Await.result(future2, Duration.Inf)
```
]

.thirty-seven-right[.center[
<img src="../img/foundation/future-sequential.svg" alt="Future sequential" style="width:300px;"/>
]]