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Task/Euler-method/Futhark/euler-method.futhark

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+fun analytic(t0: f64) (time: f64): f64 =
+  20.0 + (t0 - 20.0) * exp64(-0.07*time)
+
+fun cooling(_time: f64) (temperature: f64): f64 =
+  -0.07 * (temperature-20.0)
+
+fun main(t0: f64) (a: f64) (b: f64) (h: f64): []f64 =
+  let steps = int((b-a)/h)
+  let temps = replicate steps 0.0
+  loop ((t,temps)=(t0,temps)) = for i < steps do
+    let x = a + f64(i) * h
+    let temps[i] = abs(t-analytic t0 x)
+    in (t + h * cooling x t,
+        temps)
+ in temps