RC

abstract_type.nim

@@ -0,0 +1,11 @@
+# In Nimrod type classes can be seen as an abstract type. Type classes specify
+# interfaces, which can be instantiated by concrete types.
+type
+  Comparable = generic x, y
+    (x < y) is bool
+
+  Container[T] = generic c
+    c.len is ordinal
+    items(c) is iterator
+    for value in c:
+      type(value) is T

boxthecompass.nim

@@ -1,4 +1,4 @@
-import strutils, strfmt
+import strfmt
 
 const names = [
   "North", "North by east", "North-northeast", "Northeast by north",
@@ -15,4 +15,4 @@ for i in 0..32:
   var d = float(i) * 11.25
   if i mod 3 == 1: d += 5.62
   if i mod 3 == 2: d -= 5.62
-  printlnfmt("{:2} {:18} {:>6}", j + 1, names[j], d.formatFloat(ffDecimal, 2))
+  printlnfmt "{:2} {:18} {:>6.2f}", j + 1, names[j], d

collections.nim

@@ -0,0 +1,66 @@
+# Array
+# Length is known at compile time
+var a = [1,2,3,4,5,6,7,8,9]
+var b: array[128, int]
+b[9] = 10
+b[0..8] = a
+var c: array['a'..'d', float] = [1.0, 1.1, 1.2, 1.3]
+c['b'] = 10000
+
+# Seq
+# Variable length sequences
+var d = @[1,2,3,5,6,7,8,9]
+d.add(10)
+d.add([11,12,13,14])
+d[0] = 0
+
+var e: seq[float] = @[]
+e.add(15.5)
+
+var f = newSeq[string]()
+f.add("foo")
+f.add("bar")
+
+# Tuples
+# Fixed length, named
+var g = (13, 13, 14)
+g[0] = 12
+
+var h: tuple[key: string, val: int] = ("foo", 100)
+
+# A sequence of key-val tuples:
+var i = {"foo": 12, "bar": 13}
+
+# Set
+# Bit vector of ordinals
+var j: set[char]
+j.incl('X')
+
+var k = {'a'..'z', '0'..'9'}
+
+j = j + k
+
+# Tables
+# Hash tables (there are also ordered hash tables and counting hash tables)
+import tables
+var l = initTable[string, int]()
+l["foo"] = 12
+l["bar"] = 13
+
+var m = {"foo": 12, "bar": 13}.toTable
+m["baz"] = 14
+
+# Sets
+# Hash sets (also ordered hash sets)
+import sets
+var n = initSet[string]()
+n.incl("foo")
+
+var o = ["foo", "bar", "baz"].toSet
+o.incl("foobar")
+
+# Queues
+import queues
+var p = initQueue[int]()
+p.add(12)
+p.add(13)

meanangle.nim

@@ -1,6 +1,4 @@
-import math, complex, strutils
-
-#const mpi: cdouble = 3.14159265358979323846
+import math, complex
 
 proc rect(r, phi): TComplex = (r * cos(phi), sin(phi))
 proc phase(c): float = arctan2(c.im, c.re)
@@ -14,27 +12,6 @@ proc meanAngle(deg): float =
     c += rect(1.0, radians(d))
   degrees(phase(c / float(deg.len)))
 
-#proc meanAngle(angles): float =
-#  var c: TComplex
-#  for d in angles:
-#    c = c + rect(1.0, radians(d))
-#    echo c
-#
-#  echo (c / float(angles.len))
-#  echo phase(c / float(angles.len))
-#  degrees(phase(c / float(angles.len)))
-
-#proc meanAngle(angles): cdouble =
-#  var xPart, yPart: cdouble = 0
-#  for i in 0 .. < angles.len:
-#    echo cos(angles[i] * pi / 180)
-#    xPart += cos(angles[i] * pi / 180)
-#    yPart += sin(angles[i] * pi / 180)
-#    echo angles[i], " ", xPart, " ", yPart
-#  echo yPart / float(angles.len), " ", xPart / float(angles.len)
-#  echo arctan2(yPart / float(angles.len), xPart / float(angles.len))
-#  arctan2(yPart / float(angles.len), xPart / float(angles.len)) * 180 / pi
-
-echo "The 1st mean angle is: ", formatFloat(meanAngle([350.0, 10.0]), ffDecimal, 1), " degrees"
-echo "The 2nd mean angle is: ", formatFloat(meanAngle([90.0, 180.0, 270.0, 360.0]), ffDecimal, 1), " degrees"
-echo "The 3rd mean angle is: ", formatFloat(meanAngle([10.0, 20.0, 30.0]), ffDecimal, 1), " degrees"
+echo "The 1st mean angle is: ", meanAngle([350.0, 10.0]), " degrees"
+echo "The 2nd mean angle is: ", meanAngle([90.0, 180.0, 270.0, 360.0]), " degrees"
+echo "The 3rd mean angle is: ", meanAngle([10.0, 20.0, 30.0]), " degrees"

menu.nim

@@ -0,0 +1,22 @@
+import strutils, rdstdin
+
+proc menu(xs) =
+  for i,x in xs: echo "  ",i,") ",x
+
+proc ok(reply, count): bool =
+  try:
+    let n = parseInt(reply)
+    return 0 <= n and n < count
+  except: return false
+
+proc selector(xs, prompt): string =
+  if xs.len == 0: return ""
+  var reply = "-1"
+  while not ok(reply, xs.len):
+    menu(xs)
+    reply = readLineFromStdin(prompt).strip()
+  return xs[parseInt(reply)]
+
+const xs = ["fee fie", "huff and puff", "mirror mirror", "tick tock"]
+let item = selector(xs, "Which is from the three pigs: ")
+echo "You chose: ", item

middlethreedigits.nim

@@ -0,0 +1,16 @@
+import math
+
+proc middleThreeDigits(i): auto =
+  var s = $abs(i)
+  if s.len < 3 or s.len mod 2 == 0:
+    raise newException(EInvalidValue, "Need odd and >= 3 digits")
+  let mid = s.len div 2
+  return s[mid-1..mid+1]
+
+const passing = @[123, 12345, 1234567, 987654321, 10001, -10001, -123, -100, 100, -12345]
+const failing = @[1, 2, -1, -10, 2002, -2002, 0]
+
+for i in passing & failing:
+  var answer = try: middleThreeDigits(i)
+    except EInvalidValue: getCurrentExceptionMsg()
+  echo "middleThreeDigits(",i,") returned: ",answer

min.nim

@@ -0,0 +1,5 @@
+proc reversed(x) =
+  for i in countdown(x.high, x.low):
+    echo i
+
+reversed(@[-19, 7, -4, 6])

montecarlo.nim

@@ -0,0 +1,12 @@
+import math
+randomize()
+
+proc pi(nthrows): float =
+  var inside = 0
+  for i in 1..int64(nthrows):
+    if hypot(random(1.0), random(1.0)) < 1:
+      inc inside
+  return float(4 * inside) / nthrows
+
+for n in [10e4, 10e6, 10e7, 10e8]:
+  echo pi(n)

nondecimalradicesinput.nim

@@ -0,0 +1,9 @@
+import strutils
+
+echo parseInt "10"       # 10
+
+echo parseHexInt "0x10"  # 16
+echo parseHexInt "10"    # 16
+
+echo parseOctInt "0o120" # 80
+echo parseOctInt "120"   # 80

nondecimalradicesoutput.nim

@@ -0,0 +1,4 @@
+import strutils
+
+for i in 0..33:
+  echo toBin(i, 6)," ",toOct(i, 3)," ",align($i,2)," ",toHex(i,2)

reversednew.nim

@@ -0,0 +1,28 @@
+iterator reversed(x: seq[char]) =
+  for i in countdown(x.high, x.low):
+    yield x[i]
+
+var ar = ['a','b','c','d']
+var sq = @['a','b','c','d']
+var st = "abcd"
+
+for i in ar: stdout.write i," "
+echo ""
+for i in sq: stdout.write i," "
+echo ""
+for i in st: stdout.write i," "
+echo ""
+
+for i,x in ar: stdout.write i," ",x," "
+echo ""
+for i,x in sq: stdout.write i," ",x," "
+echo ""
+for i,x in st: stdout.write i," ",x," "
+echo ""
+
+#for i in reversed(ar): stdout.write i," "
+#echo ""
+for i in reversed(sq): stdout.write i," "
+echo ""
+#for i in st: stdout.write i," "
+#echo ""