"// This function adds two numbers.\nfn add(a, b) {\n return a + b\n}\n\n// This function adds an array of numbers.\n// It uses the `reduce` function, to call the `add` function on every\n// element of the `arr` parameter. The starting value is 0.\nfn sum(arr) {\n return reduce(arr, 0, add)\n}\n\n/* The above is basically like this pseudo-code:\nfn sum(arr):\n sumSoFar = 0\n for i in arr:\n sumSoFar = add(sumSoFar, i)\n return sumSoFar */\n\n\n// We use `assertEqual` to check that our `sum` function gives the\n// expected result. It's good to check your work!\nassertEqual(sum([1, 2, 3]), 6, 0.00001, \"1 + 2 + 3 summed is 6\")",
"// This example works just like the previous example above, but it uses\n// an anonymous `add` function as its parameter, instead of declaring a\n// named function outside.\narr = [1, 2, 3]\nsum = reduce(arr, 0, fn(i, result_so_far) {\n return i + result_so_far\n})\n\n// We use `assertEqual` to check that our `sum` function gives the\n// expected result. It's good to check your work!\nassertEqual(sum, 6, 0.00001, \"1 + 2 + 3 summed is 6\")",
"// Declare a function that sketches a decagon.\nfn decagon(radius) {\n // Each side of the decagon is turned this many degrees from the previous angle.\n stepAngle = 1 / 10 * tau()\n\n // Start the decagon sketch at this point.\n startOfDecagonSketch = startSketchOn('XY')\n |> startProfileAt([cos(0) * radius, sin(0) * radius], %)\n\n // Use a `reduce` to draw the remaining decagon sides.\n // For each number in the array 1..10, run the given function,\n // which takes a partially-sketched decagon and adds one more edge to it.\n fullDecagon = reduce([1..10], startOfDecagonSketch, fn(i, partialDecagon) {\n // Draw one edge of the decagon.\n x = cos(stepAngle * i) * radius\n y = sin(stepAngle * i) * radius\n return lineTo([x, y], partialDecagon)\n })\n\n return fullDecagon\n}\n\n/* The `decagon` above is basically like this pseudo-code:\nfn decagon(radius):\n stepAngle = (1/10) * tau()\n plane = startSketchOn('XY')\n startOfDecagonSketch = startProfileAt([(cos(0)*radius), (sin(0) * radius)], plane)\n\n // Here's the reduce part.\n partialDecagon = startOfDecagonSketch\n for i in [1..10]:\n x = cos(stepAngle * i) * radius\n y = sin(stepAngle * i) * radius\n partialDecagon = lineTo([x, y], partialDecagon)\n fullDecagon = partialDecagon // it's now full\n return fullDecagon */\n\n\n// Use the `decagon` function declared above, to sketch a decagon with radius 5.\ndecagon(5.0)\n |> close(%)"
"// Declare a function that sketches a decagon.\nfn decagon(radius) {\n // Each side of the decagon is turned this many degrees from the previous angle.\n stepAngle = 1 / 10 * TAU\n\n // Start the decagon sketch at this point.\n startOfDecagonSketch = startSketchOn('XY')\n |> startProfileAt([cos(0) * radius, sin(0) * radius], %)\n\n // Use a `reduce` to draw the remaining decagon sides.\n // For each number in the array 1..10, run the given function,\n // which takes a partially-sketched decagon and adds one more edge to it.\n fullDecagon = reduce([1..10], startOfDecagonSketch, fn(i, partialDecagon) {\n // Draw one edge of the decagon.\n x = cos(stepAngle * i) * radius\n y = sin(stepAngle * i) * radius\n return lineTo([x, y], partialDecagon)\n })\n\n return fullDecagon\n}\n\n/* The `decagon` above is basically like this pseudo-code:\nfn decagon(radius):\n stepAngle = (1/10) * TAU\n plane = startSketchOn('XY')\n startOfDecagonSketch = startProfileAt([(cos(0)*radius), (sin(0) * radius)], plane)\n\n // Here's the reduce part.\n partialDecagon = startOfDecagonSketch\n for i in [1..10]:\n x = cos(stepAngle * i) * radius\n y = sin(stepAngle * i) * radius\n partialDecagon = lineTo([x, y], partialDecagon)\n fullDecagon = partialDecagon // it's now full\n return fullDecagon */\n\n\n// Use the `decagon` function declared above, to sketch a decagon with radius 5.\ndecagon(5.0)\n |> close(%)"
]
},
{
@ -207096,7 +207096,7 @@
{
"name":"tau",
"summary":"Return the value of `tau`. The full circle constant (τ). Equal to 2π.",
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Nick Cameron