Price fraction: Difference between revisions

=={{header|Julia}}==

This solution is somewhat straightforward but does highlight a couple of Julia features. The interval cut-offs and values are exactly represented by rational numbers. The interval to which an input value belongs is identified by applying the <code>findfirst</code> (true value) function to an element-wise comparison (<code>.&lt;</code>) of this value to the cut-off array.

<lang Julia>

const PFCUT = [6:5:101]//100

const PFVAL = [10:8:26, 32:6:50, 54:4:98, 100]//100

function pricefraction{T<:FloatingPoint}(a::T)

zero(T) <= a || error("a = ", a, ", but it must be >= 0.")

a <= one(T) || error("a = ", a, ", but it must be <= 1.")

convert(T, PFVAL[findfirst(a .< PFCUT)])

end

test = [0.:0.05:1., 0.51, 0.56, 0.61, rand(), rand(), rand(), rand()]

println("Testing the price fraction function")

for t in test

println(@sprintf " %.4f -> %.4f" t pricefraction(t))

end

</lang>

{{out}}

<pre>

Testing the price fraction function

0.0000 -> 0.1000

0.0500 -> 0.1000

0.1000 -> 0.1800

0.1500 -> 0.2600

0.2000 -> 0.3200

0.2500 -> 0.3800

0.3000 -> 0.4400

0.3500 -> 0.5000

0.4000 -> 0.5400

0.4500 -> 0.5800

0.5000 -> 0.6200

0.5500 -> 0.6600

0.6000 -> 0.7000

0.6500 -> 0.7400

0.7000 -> 0.7800

0.7500 -> 0.8200

0.8000 -> 0.8600

0.8500 -> 0.9000

0.9000 -> 0.9400

0.9500 -> 0.9800

1.0000 -> 1.0000

0.5100 -> 0.6600

0.5600 -> 0.7000

0.6100 -> 0.7400

0.5603 -> 0.7000

0.9812 -> 1.0000

0.5127 -> 0.6600

0.4821 -> 0.6200

</pre>