さまざまな言語で数値計算
Only Do What Only You Can Do
エルミート補間
2個の関数値 $ f(x_0), f(x_1) $ と, それぞれの微分係数 $ f'(x_0), f'(x_1) $ とを与えられたとき, 与えられた2個の関数値を通る3次式を求めるには, まず次のような表を作る.
このとき,
あとは, ニュートン補間と同じ.
第$n$差分商を
で表すと, 与えられた $n$点を通る $2n-1$次式は次のように表すことができる.
この式を使って, 与えられた点以外の点の値を求める.
例題として,
を近似する.
VBScript
Option Explicit 'データ点の数 - 1 Private Const N = 6 Private Const Nx2 = 13 Dim x(): ReDim x(N) Dim y(): ReDim y(N) Dim yd(): ReDim yd(N) '1.5刻みで -4.5~4.5 まで, 7点だけ値をセット Dim i For i = 0 To N Dim d1: d1 = i * 1.5 - 4.5 x(i) = d1 y(i) = f(d1) yd(i) = fd(d1) Next '差分商の表を作る Dim z(): ReDim z(Nx2) Dim d(): ReDim d(Nx2, Nx2) For i = 0 To Nx2 Dim j: j = i \ 2 z(i) = x(j) d(0,i) = y(j) Next For i = 1 To Nx2 For j = 0 To (Nx2 - i) If i = 1 And j Mod 2 = 0 Then d(i,j) = yd(j \ 2) Else d(i,j) = (d(i-1,j+1) - d(i-1,j)) / (z(j+i) - z(j)) End If Next Next 'n階差分商 Dim a(): ReDim a(Nx2) For j = 0 To Nx2 a(j) = d(j,0) Next '0.5刻みで 与えられていない値を補間 For i = 0 To 18 d1 = i * 0.5 - 4.5 Dim d2: d2 = f(d1) Dim d3: d3 = hermite(d1, z, a) '元の関数と比較 WScript.StdOut.Write Right(Space(5) & FormatNumber(d1, 2, -1, 0, 0), 5) & vbTab WScript.StdOut.Write Right(Space(8) & FormatNumber(d2, 5, -1, 0, 0), 8) & vbTab WScript.StdOut.Write Right(Space(8) & FormatNumber(d3, 5, -1, 0, 0), 8) & vbTab WScript.StdOut.WriteLine Right(Space(8) & FormatNumber(d2 - d3, 5, -1, 0, 0), 8) Next '元の関数 Private Function f(ByVal x) f = x - (x ^ 3) / (3 * 2) + (x ^ 5) / (5 * 4 * 3 * 2) End Function '導関数 Private Function fd(ByVal x) fd = 1 - (x ^ 2) / 2 + (x ^ 4) / (4 * 3 * 2) End Function 'Hermite (エルミート) 補間 Private Function hermite(ByVal d, ByVal z(), ByVal a()) Dim sum: sum = a(0) Dim i, j For i = 1 To Nx2 Dim prod: prod = a(i) For j = 0 To (i - 1) If j <> i Then prod = prod * (d - z(j)) End If Next sum = sum + prod Next hermite = sum End Function
Z:\>cscript //nologo Z:\0704.vbs -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 -0.00000 0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 -0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 -0.00000 4.50 4.68984 4.68984 -0.00000
JScript
// データ点の数 var N = 7 var Nx2 = 14 var x = [] var y = [] var yd = [] // 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット for (var i = 0; i < N; i++) { var d1 = i * 1.5 - 4.5 x[i] = d1 y[i] = f(d1) yd[i] = fd(d1) } // 差分商の表を作る var z = [] var d = [] d[0] = [] for (var i = 0; i < Nx2; i++) { var j = parseInt(i / 2) z[i] = x[j] d[0][i] = y[j] } for (var i = 1; i < Nx2; i++) { d[i] = [] for (var j = 0; j < Nx2 - i; j++) { if (i == 1 && j % 2 == 0) d[i][j] = yd[parseInt(j / 2)] else d[i][j] = (d[i-1][j+1] - d[i-1][j]) / (z[j+i] - z[j]) } } // n階差分商 var a = [] for (var j = 0; j < Nx2; j++) a[j] = d[j][0] // 0.5刻みで 与えられていない値を補間 for (var i = 0; i <= 18; i++) { var d1 = i * 0.5 - 4.5 var d2 = f(d1) var d3 = hermite(d1, z, a) // 元の関数と比較 WScript.StdOut.Write((" " + d1.toFixed(2) ).slice(-5) + "\t") WScript.StdOut.Write((" " + d2.toFixed(5) ).slice(-8) + "\t") WScript.StdOut.Write((" " + d3.toFixed(5) ).slice(-8) + "\t") WScript.StdOut.Write((" " + (d2 - d3).toFixed(5)).slice(-8) + "\n") } // 元の関数 function f(x) { return x - Math.pow(x,3) / (3 * 2) + Math.pow(x,5) / (5 * 4 * 3 * 2) } // 導関数 function fd(x) { return 1 - Math.pow(x,2) / 2 + Math.pow(x,4) / (4 * 3 * 2) } // Hermite (エルミート) 補間 function hermite(d, z, a) { var sum = a[0] for (var i = 1; i < Nx2; i++) { var prod = a[i] for (var j = 0; j < i; j++) prod *= (d - z[j]) sum += prod } return sum }
Z:\>cscript //nologo Z:\0704.js -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 -0.00000 0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 -0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 -0.00000 4.50 4.68984 4.68984 -0.00000
PowerShell
# データ点の数 set-variable -option constant -name N -value 7 set-variable -option constant -name Nx2 -value 14 # 元の関数 function f($x) { $x - [Math]::Pow($x, 3) / (3 * 2) + [Math]::Pow($x, 5) / (5 * 4 * 3 * 2) } # 導関数 function fd($x) { 1 - [Math]::Pow($x, 2) / 2 + [Math]::Pow($x, 4) / (4 * 3 * 2) } # Hermite (エルミート) 補間 function hermite($d, $z, $a) { $sum = $a[0] foreach ($i in 1..($Nx2 - 1)) { $prod = $a[$i] foreach ($j in 0..($i - 1)) { $prod *= ($d - $z[$j]) } $sum += $prod } $sum } $x = New-Object double[] $N $y = New-Object double[] $N $yd = New-Object double[] $N # 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット foreach ($i in 0..($N - 1)) { $d1 = $i * 1.5 - 4.5 $x[$i] = $d1 $y[$i] = f($d1) $yd[$i] = fd($d1) } # 差分商の表を作る $z = New-Object double[] $Nx2 $d = New-Object "double[,]" $Nx2,$Nx2 foreach ($i in 0..($Nx2 - 1)) { $j = [Math]::Floor($i / 2) $z[$i] = $x[$j] $d[0,$i] = $y[$j] } foreach ($i in 1..($Nx2 - 1)) { foreach ($j in 0..($Nx2 - $i - 1)) { if ($i -eq 1 -and $j % 2 -eq 0) { $d[$i,$j] = $yd[[Math]::Floor($j / 2)] } else { $d[$i,$j] = ($d[($i-1),($j+1)] - $d[($i-1),$j]) / ($z[($j+$i)] - $z[$j]) } } } # n階差分商 $a = New-Object double[] $Nx2 foreach ($j in 0..($Nx2 - 1)) { $a[$j] = $d[$j,0] } # 0.5刻みで 与えられていない値を補間 foreach ($i in 0..18) { $d1 = $i * 0.5 - 4.5 $d2 = f($d1) $d3 = (hermite $d1 $z $a) # 元の関数と比較 Write-Host ([String]::Format("{0,5:F2}`t{1,8:F5}`t{2,8:F5}`t{3,8:F5}", $d1, $d2, $d3, ($d2 - $d3))) }
Z:\>powershell -file Z:\0704.ps1 -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 0.00000 0.00000 0.50 0.47943 0.47943 0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 0.00000 4.50 4.68984 4.68984 0.00000
Perl
# データ点の数 - 1 use constant N => 6; use constant Nx2 => 13; my @x = (); my @y = (); my @yd = (); # 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット for $i (0..N) { my $d1 = $i * 1.5 - 4.5; $x[$i] = $d1; $y[$i] = f($d1); $yd[$i] = fd($d1); } # 差分商の表を作る my @z = (); my @d = (); for $i (0..Nx2) { $j = int($i / 2); $z[$i] = $x[$j]; $d[0][$i] = $y[$j]; } for $i (1..Nx2) { for $j (0..(Nx2 - $i)) { if ($i == 1 && $j % 2 == 0) { $d[$i][$j] = $yd[int($j / 2)]; } else { $d[$i][$j] = ($d[$i-1][$j+1] - $d[$i-1][$j]) / ($z[$j+$i] - $z[$j]); } } } # n階差分商 my @a = (); for $j (0..Nx2) { $a[$j] = $d[$j][0]; } # 0.5刻みで 与えられていない値を補間 for $i (0..18) { my $d1 = $i * 0.5 - 4.5; my $d2 = f($d1); my $d3 = hermite($d1, \@z, \@a); # 元の関数と比較 printf("%5.2f\t%8.5f\t%8.5f\t%8.5f\n", $d1, $d2, $d3, $d2 - $d3); } # 元の関数 sub f { my ($x) = @_; $x - ($x ** 3) / (3 * 2) + ($x ** 5) / (5 * 4 * 3 * 2); } # 導関数 sub fd { my ($x) = @_; 1 - ($x ** 2) / 2 + ($x ** 4) / (4 * 3 * 2); } # Hermite (エルミート) 補間 sub hermite { my ($d, $z, $a) = @_; my $sum = $$a[0]; for $i (1..Nx2) { my $prod = $$a[$i]; for $j (0..($i - 1)) { $prod *= ($d - $$z[$j]); } $sum += $prod; } $sum; }
Z:\>perl Z:\0704.pl -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 -0.00000 0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 -0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 -0.00000 4.50 4.68984 4.68984 -0.00000
PHP
<?php # データ点の数 - 1 define("N", 6); define("Nx2", 13); $x = array(); $y = array(); $yd = array(); # 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット foreach (range(0, N) as $i) { $d1 = $i * 1.5 - 4.5; $x[$i] = $d1; $y[$i] = f($d1); $yd[$i] = fd($d1); } # 差分商の表を作る $z = array(); $d = array(); foreach (range(0, Nx2) as $i) { $j = (int)($i / 2); $z[$i] = $x[$j]; $d[0][$i] = $y[$j]; } foreach (range(1, Nx2) as $i) { foreach (range(0, Nx2 - $i) as $j) { if ($i == 1 && $j % 2 == 0) $d[$i][$j] = $yd[(int)($j / 2)]; else $d[$i][$j] = ($d[$i-1][$j+1] - $d[$i-1][$j]) / ($z[$j+$i] - $z[$j]); } } # n階差分商 $a = array(); foreach (range(0, Nx2) as $j) { $a[$j] = $d[$j][0]; } # 0.5刻みで 与えられていない値を補間 foreach (range(0, 18) as $i) { $d1 = $i * 0.5 - 4.5; $d2 = f($d1); $d3 = hermite($d1, $z, $a); # 元の関数と比較 printf("%5.2f\t%8.5f\t%8.5f\t%8.5f\n", $d1, $d2, $d3, $d2 - $d3); } # 元の関数 function f($x) { return $x - pow($x, 3) / (3 * 2) + pow($x, 5) / (5 * 4 * 3 * 2); } # 導関数 function fd($x) { return 1 - pow($x, 2) / 2 + pow($x, 4) / (4 * 3 * 2); } # Hermite (エルミート) 補間 function hermite($d, $z, $a) { $sum = $a[0]; foreach (range(1, Nx2) as $i) { $prod = $a[$i]; foreach (range(0, $i - 1) as $j) { $prod *= ($d - $z[$j]); } $sum += $prod; } return $sum; } ?>
Z:\>php Z:\0704.php -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 -0.00000 0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 -0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 -0.00000 4.50 4.68984 4.68984 -0.00000
Python
# coding: Shift_JIS # データ点の数 N = 7 Nx2 = 14 # 元の関数 def f(x): return x - (x ** 3) / (3 * 2) + (x ** 5) / (5 * 4 * 3 * 2) # 導関数 def fd(x): return 1 - (x ** 2) / 2 + (x ** 4) / (4 * 3 * 2) # Hermite (エルミート) 補間 def hermite(d, z, a): sum = a[0] for i in range(1, Nx2): prod = a[i] for j in range(0, i): prod *= (d - z[j]) sum += prod return sum x = [0 for i in range(N)] y = [0 for i in range(N)] yd = [0 for i in range(N)] # 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット for i in range(0, N): d = i * 1.5 - 4.5 x[i] = d y[i] = f(d) yd[i] = fd(d) # 差分商の表を作る z = [0 for i in range(Nx2)] d = [[0 for j in range(Nx2)] for i in range(Nx2)] for i in range(0, Nx2): j = int(i / 2) z[i] = x[j] d[0][i] = y[j] for i in range(1, Nx2): for j in range(0, Nx2 - i): if (i == 1 and j % 2 == 0): d[i][j] = yd[int(j / 2)] else: d[i][j] = (d[i-1][j+1] - d[i-1][j]) / (z[j+i] - z[j]) # n階差分商 a = [0 for i in range(Nx2)] for j in range(0, Nx2): a[j] = d[j][0] # 0.5刻みで 与えられていない値を補間 for i in range(0, 19): d1 = i * 0.5 - 4.5 d2 = f(d1) d3 = hermite(d1, z, a) # 元の関数と比較 print "%5.2f\t%8.5f\t%8.5f\t%8.5f" % (d1, d2, d3, d2 - d3)
Z:\>python Z:\0704.py -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 -0.00000 0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 -0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 -0.00000 4.50 4.68984 4.68984 -0.00000
Ruby
# データ点の数 - 1 N = 6 Nx2 = 13 # 元の関数 def f(x) x - (x ** 3) / (3 * 2) + (x ** 5) / (5 * 4 * 3 * 2) end # 導関数 def fd(x) 1 - (x ** 2) / 2 + (x ** 4) / (4 * 3 * 2) end # Hermite (エルミート) 補間 def hermite(d, z, a) sum = a[0] (1..Nx2).each do |i| prod = a[i] (0..(i - 1)).each do |j| if j != i prod *= (d - z[j]) end end sum += prod end sum end x = Array.new(N) y = Array.new(N) yd = Array.new(N) # 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット (0..N).each do |i| d = i * 1.5 - 4.5 x[i] = d y[i] = f(d) yd[i] = fd(d) end # 差分商の表を作る z = Array.new(Nx2) d = Array.new(Nx2+1) { Array.new(Nx2) } (0..Nx2).each do |i| j = i / 2 z[i] = x[j] d[0][i] = y[j] end (1..Nx2).each do |i| (0..(Nx2-i)).each do |j| if i == 1 && j % 2 == 0 d[i][j] = yd[j / 2] else d[i][j] = (d[i-1][j+1] - d[i-1][j]) / (z[j+i] - z[j]) end end end # n階差分商 a = Array.new(Nx2) (0..Nx2).each do |j| a[j] = d[j][0] end # 0.5刻みで 与えられていない値を補間 (0..18).each do |i| d1 = i * 0.5 - 4.5 d2 = f(d1) d3 = hermite(d1, z, a) # 元の関数と比較 printf("%5.2f\t%8.5f\t%8.5f\t%8.5f\n", d1, d2, d3, d2 - d3) end
Z:\>ruby Z:\0704.rb -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 -0.00000 0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 -0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 -0.00000 4.50 4.68984 4.68984 -0.00000
Groovy
Pascal
program Pas0704(arg); {$MODE delphi} uses SysUtils, Math; const // データ点の数 - 1 N = 6; Nx2 = 13; // 元の関数 function f(x:Double):Double; begin result := x - power(x,3) / (3 * 2) + power(x,5) / (5 * 4 * 3 * 2); end; // 導関数 function fd(x:Double):Double; begin result := 1 - power(x,2) / 2 + power(x,4) / (4 * 3 * 2); end; // Hermite (エルミート) 補間 function hermite(d:Double; z:array of Double; a:array of Double):Double; var sum, prod :Double; i, j :Integer; begin sum := a[0]; for i := 1 to High(a) do begin prod := a[i]; for j := Low(z) to i-1 do prod := prod * (d - z[j]); sum := sum + prod; end; result := sum; end; var i, j :Integer; x :array [0..N] of Double; y :array [0..N] of Double; yd :array [0..N] of Double; z :array [0..Nx2] of Double; a :array [0..Nx2] of Double; d :array [0..Nx2, 0..Nx2] of Double; d1, d2, d3 :Double; begin // 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット for i := Low(x) to High(x) do begin d1 := i * 1.5 - 4.5; x[i] := d1; y[i] := f(d1); yd[i] := fd(d1); end; // 差分商の表を作る for i := Low(z) to High(z) do begin j := i div 2; z[i] := x[j]; d[0,i] := y[j]; end; for i := 1 to High(z) do begin for j := Low(z) to High(z)-i do begin if (i = 1) and (j mod 2 = 0) then d[i,j] := yd[j div 2] else d[i,j] := (d[i-1,j+1] - d[i-1,j]) / (z[j+i] - z[j]); end; end; // n階差分商 for j := Low(a) to High(a) do a[j] := d[j,0]; // 0.5刻みで 与えられていない値を補間 for i := 0 to 18 do begin d1 := i * 0.5 - 4.5; d2 := f(d1); d3 := hermite(d1, z, a); // 元の関数と比較 writeln(format('%5.2f'#9'%8.5f'#9'%8.5f'#9'%8.5f', [d1, d2, d3, d2 - d3])); end; end.
Z:\>fpc -v0 -l- Pas0704.pp Z:\>Pas0704 -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 0.00000 0.00000 0.50 0.47943 0.47943 0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 0.00000 4.50 4.68984 4.68984 0.00000
Ada
with TEXT_IO, Ada.Long_Float_Text_IO; use TEXT_IO, Ada.Long_Float_Text_IO; procedure Ada0704 is -- データ点の数 - 1 N : Constant Integer := 6; Nx2 : Constant Integer := 13; type Long_Float_ArrayN is array (0..N) of Long_Float; type Long_Float_ArrayNx2 is array (0..Nx2) of Long_Float; x : Long_Float_ArrayN; y : Long_Float_ArrayN; yd : Long_Float_ArrayN; z : Long_Float_ArrayNx2; a : Long_Float_ArrayNx2; d : array (0..Nx2, 0..Nx2) of Long_Float; d1, d2, d3 : Long_Float; k : Integer; -- 元の関数 function f(x:Long_Float) return Long_Float is begin return x - Long_Float(x ** 3) / Long_Float(3 * 2) + Long_Float(x ** 5) / Long_Float(5 * 4 * 3 * 2); end f; -- 導関数 function fd(x:Long_Float) return Long_Float is begin return 1.0 - Long_Float(x ** 2) / Long_Float(2) + Long_Float(x ** 4) / Long_Float(4 * 3 * 2); end fd; -- Hermite (エルミート) 補間 function hermite(d:Long_Float; z:Long_Float_ArrayNx2; a:Long_Float_ArrayNx2) return Long_Float is sum, prod :Long_Float; begin sum := a(0); for i in 1 .. a'Last loop prod := a(i); for j in z'First .. i-1 loop prod := prod * (d - z(j)); end loop; sum := sum + prod; end loop; return sum; end; begin -- 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット for i in x'Range loop d1 := Long_Float(i) * 1.5 - 4.5; x(i) := d1; y(i) := f(d1); yd(i) := fd(d1); end loop; -- 差分商の表を作る for i in z'Range loop k := i / 2; z(i) := x(k); d(0,i) := y(k); end loop; for i in 1 .. z'Last loop for j in z'First .. z'Last-i loop if (i = 1) and (j mod 2 = 0) then d(i,j) := yd(j / 2); else d(i,j) := (d(i-1,j+1) - d(i-1,j)) / (z(j+i) - z(j)); end if; end loop; end loop; -- n階差分商 for j in a'Range loop a(j) := d(j,0); end loop; -- 0.5刻みで 与えられていない値を補間 for i in 0..18 loop d1 := Long_Float(i) * 0.5 - 4.5; d2 := f(d1); d3 := hermite(d1, z, a); -- 元の関数と比較 Put(d1, Fore=>2, Aft=>2, Exp=>0); Put(Ascii.HT); Put(d2, Fore=>3, Aft=>5, Exp=>0); Put(Ascii.HT); Put(d3, Fore=>3, Aft=>5, Exp=>0); Put(Ascii.HT); Put(d2 - d3, Fore=>3, Aft=>5, Exp=>0); New_Line; end loop; end Ada0704;
xxxxxx@yyyyyy /Z $ gnatmake Ada0704.adb xxxxxx@yyyyyy /Z $ Ada0704 -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 -0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 0.00000 -0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 -0.00000 1.50 1.00078 1.00078 -0.00000 2.00 0.93333 0.93333 -0.00000 2.50 0.70964 0.70964 -0.00000 3.00 0.52500 0.52500 -0.00000 3.50 0.73099 0.73099 -0.00000 4.00 1.86667 1.86667 -0.00000 4.50 4.68984 4.68984 -0.00000
VB.NET
Module VB0704 'データ点の数 - 1 Private Const N As Integer = 6 Private Const Nx2 As Integer = 13 Public Sub Main() Dim x(N) As Double Dim y(N) As Double Dim yd(N) As Double '1.5刻みで -4.5~4.5 まで, 7点だけ値をセット For i As Integer = 0 To N Dim d1 As Double = i * 1.5 - 4.5 x(i) = d1 y(i) = f(d1) yd(i) = fd(d1) Next '差分商の表を作る Dim z(Nx2) As Double Dim d(Nx2, Nx2) As Double For i As Integer = 0 To Nx2 Dim j As Integer = i \ 2 z(i) = x(j) d(0,i) = y(j) Next For i As Integer = 1 To Nx2 For j As Integer = 0 To (Nx2 - i) If i = 1 AndAlso j Mod 2 = 0 Then d(i,j) = yd(j \ 2) Else d(i,j) = (d(i-1,j+1) - d(i-1,j)) / (z(j+i) - z(j)) End If Next Next 'n階差分商 Dim a(Nx2) As Double For j As Integer = 0 To Nx2 a(j) = d(j,0) Next '0.5刻みで 与えられていない値を補間 For i As Integer = 0 To 18 Dim d1 As Double = i * 0.5 - 4.5 Dim d2 As Double = f(d1) Dim d3 As Double = hermite(d1, z, a) '元の関数と比較 Console.WriteLine(String.Format("{0,5:F2}{4}{1,8:F5}{4}{2,8:F5}{4}{3,8:F5}", d1, d2, d3, d2 - d3, vbTab)) Next End Sub '元の関数 Private Function f(ByVal x As Double) As Double Return x - (x ^ 3) / (3 * 2) + (x ^ 5) / (5 * 4 * 3 * 2) End Function '導関数 Private Function fd(ByVal x As Double) As Double Return 1 - (x ^ 2) / 2 + (x ^ 4) / (4 * 3 * 2) End Function 'Hermite (エルミート) 補間 Private Function hermite(ByVal d As Double, ByVal z() As Double, ByVal a() As Double) As Double Dim sum As Double = a(0) For i As Integer = 1 To Nx2 Dim prod As Double = a(i) For j As Integer = 0 To (i - 1) prod *= (d - z(j)) Next sum += prod Next Return sum End Function End Module
Z:\>vbc -nologo VB0704.vb Z:\>VB0704 -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 0.00000 0.00000 0.50 0.47943 0.47943 0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 0.00000 4.50 4.68984 4.68984 0.00000
C#
using System; public class CS0704 { // データ点の数 private const int N = 7; private const int Nx2 = 14; public static void Main() { double[] x = new double[N]; double[] y = new double[N]; double[] yd = new double[N]; // 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット for (int i = 0; i < N; i++) { double d1 = i * 1.5 - 4.5; x[i] = d1; y[i] = f(d1); yd[i] = fd(d1); } // 差分商の表を作る double[] z = new double[Nx2]; double[,] d = new double[Nx2,Nx2]; for (int i = 0; i < Nx2; i++) { int j = i / 2; z[i] = x[j]; d[0,i] = y[j]; } for (int i = 1; i < Nx2; i++) { for (int j = 0; j < Nx2 - i; j++) { if (i == 1 && j % 2 == 0) d[i,j] = yd[j / 2]; else d[i,j] = (d[i-1,j+1] - d[i-1,j]) / (z[j+i] - z[j]); } } // n階差分商 double[] a = new double[Nx2]; for (int j = 0; j < Nx2; j++) a[j] = d[j,0]; // 0.5刻みで 与えられていない値を補間 for (int i = 0; i <= 18; i++) { double d1 = i * 0.5 - 4.5; double d2 = f(d1); double d3 = hermite(d1, z, a); // 元の関数と比較 Console.WriteLine(string.Format("{0,5:F2}\t{1,8:F5}\t{2,8:F5}\t{3,8:F5}", d1, d2, d3, d2 - d3)); } } // 元の関数 private static double f(double x) { return x - Math.Pow(x,3) / (3 * 2) + Math.Pow(x,5) / (5 * 4 * 3 * 2); } // 導関数 private static double fd(double x) { return 1 - Math.Pow(x,2) / 2 + Math.Pow(x,4) / (4 * 3 * 2); } // Hermite (エルミート) 補間 private static double hermite(double d, double[] z, double[] a) { double sum = a[0]; for (int i = 1; i < Nx2; i++) { double prod = a[i]; for (int j = 0; j < i; j++) prod *= (d - z[j]); sum += prod; } return sum; } }
Z:\>csc -nologo CS0704.cs Z:\>CS0704 -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 0.00000 0.00000 0.50 0.47943 0.47943 0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 0.00000 4.50 4.68984 4.68984 0.00000
Java
public class Java0704 { // データ点の数 private static final int N = 7; private static final int Nx2 = 14; public static void main(String []args) { double[] x = new double[N]; double[] y = new double[N]; double[] yd = new double[N]; // 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット for (int i = 0; i < N; i++) { double d1 = i * 1.5 - 4.5; x[i] = d1; y[i] = f(d1); yd[i] = fd(d1); } // 差分商の表を作る double[] z = new double[Nx2]; double[][] d = new double[Nx2][Nx2]; for (int i = 0; i < Nx2; i++) { int j = i / 2; z[i] = x[j]; d[0][i] = y[j]; } for (int i = 1; i < Nx2; i++) { for (int j = 0; j < Nx2 - i; j++) { if (i == 1 && j % 2 == 0) d[i][j] = yd[j / 2]; else d[i][j] = (d[i-1][j+1] - d[i-1][j]) / (z[j+i] - z[j]); } } // n階差分商 double[] a = new double[Nx2]; for (int j = 0; j < Nx2; j++) a[j] = d[j][0]; // 0.5刻みで 与えられていない値を補間 for (int i = 0; i <= 18; i++) { double d1 = i * 0.5 - 4.5; double d2 = f(d1); double d3 = hermite(d1, z, a); // 元の関数と比較 System.out.println(String.format("%5.2f\t%8.5f\t%8.5f\t%8.5f", d1, d2, d3, d2 - d3)); } } // 元の関数 private static double f(double x) { return x - Math.pow(x,3) / (3 * 2) + Math.pow(x,5) / (5 * 4 * 3 * 2); } // 導関数 private static double fd(double x) { return 1 - Math.pow(x,2) / 2 + Math.pow(x,4) / (4 * 3 * 2); } // Hermite (エルミート) 補間 private static double hermite(double d, double[] z, double[] a) { double sum = a[0]; for (int i = 1; i < Nx2; i++) { double prod = a[i]; for (int j = 0; j < i; j++) prod *= (d - z[j]); sum += prod; } return sum; } }
Z:\>javac Java0704.java Z:\>java Java0704 -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 -0.00000 0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 -0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 -0.00000 4.50 4.68984 4.68984 -0.00000
C++
#include <iostream> #include <iomanip> #include <math.h> using namespace std; // データ点の数 const int N = 7; const int Nx2 = 14; // 元の関数 double f(double x); // 導関数 double fd(double x); // Hermite (エルミート) 補間 double hermite(double d, double z[], double a[]); int main() { double x[N], y[N], yd[N]; // 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット for (int i = 0; i < N; i++) { double d = i * 1.5 - 4.5; x[i] = d; y[i] = f(d); yd[i] = fd(d); } // 差分商の表を作る double z[Nx2]; double d[Nx2][Nx2]; for (int i = 0; i < Nx2; i++) { int j = i / 2; z[i] = x[j]; d[0][i] = y[j]; } for (int i = 1; i < Nx2; i++) { for (int j = 0; j < Nx2 - i; j++) { if (i == 1 && j % 2 == 0) d[i][j] = yd[j / 2]; else d[i][j] = (d[i-1][j+1] - d[i-1][j]) / (z[j+i] - z[j]); } } // n階差分商 double a[Nx2]; for (int j = 0; j < Nx2; j++) a[j] = d[j][0]; // 0.5刻みで 与えられていない値を補間 for (int i = 0; i <= 18; i++) { double d = i * 0.5 - 4.5; double d1 = f(d); double d2 = hermite(d, z, a); // 元の関数と比較 cout << setw(5) << fixed << setprecision(2) << d << '\t'; cout << setw(8) << fixed << setprecision(5) << d1 << '\t'; cout << setw(8) << fixed << setprecision(5) << d2 << '\t'; cout << setw(8) << fixed << setprecision(5) << d1 - d2 << endl; } return 0; } // 元の関数 double f(double x) { return x - pow(x,3) / (3 * 2) + pow(x,5) / (5 * 4 * 3 * 2); } // 導関数 double fd(double x) { return 1 - pow(x,2) / 2 + pow(x,4) / (4 * 3 * 2); } // Hermite (エルミート) 補間 double hermite(double d, double z[], double a[]) { double sum = a[0]; for (int i = 1; i < Nx2; i++) { double prod = a[i]; for (int j = 0; j < i; j++) prod *= (d - z[j]); sum += prod; } return sum; }
Z:\>bcc32 -q CP0704.cpp cp0704.cpp: Z:\>CP0704 -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 0.00000 -0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 -0.00000 1.50 1.00078 1.00078 -0.00000 2.00 0.93333 0.93333 -0.00000 2.50 0.70964 0.70964 -0.00000 3.00 0.52500 0.52500 -0.00000 3.50 0.73099 0.73099 -0.00000 4.00 1.86667 1.86667 -0.00000 4.50 4.68984 4.68984 -0.00000
Objective-C
#import <Foundation/Foundation.h> #import <math.h> // データ点の数 const int N = 7; const int Nx2 = 14; // 元の関数 double f(double x); // 導関数 double fd(double x); // Hermite (エルミート) 補間 double hermite(double d, double z[], double a[]); int main() { int i, j; double x[N], y[N], yd[N]; // 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット for (i = 0; i < N; i++) { double d = i * 1.5 - 4.5; x[i] = d; y[i] = f(d); yd[i] = fd(d); } // 差分商の表を作る double z[Nx2]; double d[Nx2][Nx2]; for (i = 0; i < Nx2; i++) { int j = i / 2; z[i] = x[j]; d[0][i] = y[j]; } for (i = 1; i < Nx2; i++) { for (j = 0; j < Nx2 - i; j++) { if (i == 1 && j % 2 == 0) d[i][j] = yd[j / 2]; else d[i][j] = (d[i-1][j+1] - d[i-1][j]) / (z[j+i] - z[j]); } } // n階差分商 double a[Nx2]; for (j = 0; j < Nx2; j++) a[j] = d[j][0]; // 0.5刻みで 与えられていない値を補間 for (i = 0; i <= 18; i++) { double d = i * 0.5 - 4.5; double d1 = f(d); double d2 = hermite(d, z, a); // 元の関数と比較 printf("%5.2f\t%8.5f\t%8.5f\t%8.5f\n", d, d1, d2, d1 - d2); } return 0; } // 元の関数 double f(double x) { return x - pow(x,3) / (3 * 2) + pow(x,5) / (5 * 4 * 3 * 2); } // 導関数 double fd(double x) { return 1 - pow(x,2) / 2 + pow(x,4) / (4 * 3 * 2); } // Hermite (エルミート) 補間 double hermite(double d, double z[], double a[]) { int i, j; double sum = a[0]; for (i = 1; i < Nx2; i++) { double prod = a[i]; for (j = 0; j < i; j++) prod *= (d - z[j]); sum += prod; } return sum; }
xxxxxx@yyyyyy /Z $ gcc -o OC0704 OC0704.m -lobjc -lgnustep-base -I $INCLUDE -L $LIB $CFLAGS xxxxxx@yyyyyy /Z $ OC0704 -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 -0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 0.00000 -0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 -0.00000 1.50 1.00078 1.00078 -0.00000 2.00 0.93333 0.93333 -0.00000 2.50 0.70964 0.70964 -0.00000 3.00 0.52500 0.52500 -0.00000 3.50 0.73099 0.73099 -0.00000 4.00 1.86667 1.86667 -0.00000 4.50 4.68984 4.68984 -0.00000
D
import std.stdio; import std.math; // データ点の数 const int N = 7; const int Nx2 = 14; void main(string[] args) { double x[N]; double y[N]; double yd[N]; // 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット for (int i = 0; i < N; i++) { double d = i * 1.5 - 4.5; x[i] = d; y[i] = f(d); yd[i] = fd(d); } // 差分商の表を作る double z[Nx2]; double d[Nx2][Nx2]; for (int i = 0; i < Nx2; i++) { int j = i / 2; z[i] = x[j]; d[0][i] = y[j]; } for (int i = 1; i < Nx2; i++) { for (int j = 0; j < Nx2 - i; j++) { if (i == 1 && j % 2 == 0) d[i][j] = yd[j / 2]; else d[i][j] = (d[i-1][j+1] - d[i-1][j]) / (z[j+i] - z[j]); } } // n階差分商 double a[Nx2]; for (int j = 0; j < Nx2; j++) a[j] = d[j][0]; // 0.5刻みで 与えられていない値を補間 for (int i = 0; i <= 18; i++) { double d1 = i * 0.5 - 4.5; double d2 = f(d1); double d3 = hermite(d1, z, a); // 元の関数と比較 writefln("%5.2f\t%8.5f\t%8.5f\t%8.5f", d1, d2, d3, d2 - d3); } } // 元の関数 double f(double x) { return x - pow(x,3) / (3 * 2) + pow(x,5) / (5 * 4 * 3 * 2); } // 導関数 double fd(double x) { return 1 - pow(x,2) / 2 + pow(x,4) / (4 * 3 * 2); } // Hermite (エルミート) 補間 double hermite(double d, double z[], double a[]) { double sum = a[0]; for (int i = 1; i < Nx2; i++) { double prod = a[i]; for (int j = 0; j < i; j++) prod *= (d - z[j]); sum += prod; } return sum; }
Z:\>dmd D0704.d Z:\>D0704 -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 -0.00000 0.00000 0.50 0.47943 0.47943 0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 -0.00000 3.50 0.73099 0.73099 -0.00000 4.00 1.86667 1.86667 0.00000 4.50 4.68984 4.68984 -0.00000
Go
package main import "fmt" import "math" // データ点の数 const N = 7 const Nx2 = 14 func main() { var x [N]float64 var y [N]float64 var yd [N]float64 // 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット for i := 0; i < N; i++ { var d float64 = float64(i) * 1.5 - 4.5 x[i] = d y[i] = f(d) yd[i] = fd(d) } // 差分商の表を作る var z[Nx2] float64 var d[Nx2][Nx2] float64 for i := 0; i < Nx2; i++ { j := i / 2 z[i] = x[j] d[0][i] = y[j] } for i := 1; i < Nx2; i++ { for j := 0; j < Nx2 - i; j++ { if (i == 1 && j % 2 == 0) { d[i][j] = yd[j / 2] } else { d[i][j] = (d[i-1][j+1] - d[i-1][j]) / (z[j+i] - z[j]) } } } // n階差分商 var a[Nx2] float64 for j := 0; j < Nx2; j++ { a[j] = d[j][0] } // 0.5刻みで 与えられていない値を補間 for i := 0; i <= 18; i++ { var d float64 = float64(i) * 0.5 - 4.5 var d1 float64 = f(d) var d2 float64 = hermite(d, z[:], a[:]) // 元の関数と比較 fmt.Printf("%5.2f\t%8.5f\t%8.5f\t%8.5f\n", d, d1, d2, d1 - d2) } } // 元の関数 func f(x float64) float64 { return x - math.Pow(x,3) / (3 * 2) + math.Pow(x,5) / (5 * 4 * 3 * 2) } // 導関数 func fd(x float64) float64 { return 1 - math.Pow(x,2) / 2 + math.Pow(x,4) / (4 * 3 * 2) } // Hermite (エルミート) 補間 func hermite(d float64, z []float64, a []float64) float64 { var sum float64 = a[0] for i := 1; i < Nx2; i++ { var prod float64 = a[i] for j := 0; j < i; j++ { prod *= (d - z[j]) } sum += prod } return sum }
Z:\>8g GO0704.go Z:\>8l -o GO0704.exe GO0704.8 Z:\>GO0704 -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 -0.00000 0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 -0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 -0.00000 4.50 4.68984 4.68984 -0.00000
Scala
object Scala0704 { // データ点の数 - 1 val N = 6 val Nx2 = 13 def main(args: Array[String]) { // 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット val x = (0 to N).map(_ * 1.5 - 4.5) val y = x.map(f) val yd = x.map(fd) // 差分商の表を作る val z = (0 to Nx2).map(_ / 2).map(x(_)) val d = Array.ofDim[Double](Nx2 + 1, Nx2 + 1) for (i <- 0 to Nx2) d(0)(i) = y(i / 2) for (i <- 1 to Nx2) { for (j <- 0 to Nx2 - i) if (i == 1 && j % 2 == 0) d(i)(j) = yd(j / 2) else d(i)(j) = (d(i-1)(j+1) - d(i-1)(j)) / (z(j+i) - z(j)) } // n階差分商 val a = (0 to Nx2).map(d(_)(0)) // 0.5刻みで 与えられていない値を補間 val d1 = (0 to 18).map(_ * 0.5 - 4.5) val d2 = d1.map(f) val d3 = d1.map(hermite(_, z, a)) (d1 zip d2 zip d3).foreach { case ((d1, d2), d3) => println("%5.2f\t%8.5f\t%8.5f\t%8.5f".format(d1, d2, d3, d2 - d3)) } } // 元の関数 def f(x:Double) = { x - Math.pow(x,3) / (3 * 2) + Math.pow(x,5) / (5 * 4 * 3 * 2) } // 導関数 def fd(x:Double) = { 1 - Math.pow(x,2) / 2 + Math.pow(x,4) / (4 * 3 * 2) } // Hermite (エルミート) 補間 def hermite(d:Double, z:IndexedSeq[Double], a:IndexedSeq[Double]) = { var sum_list = List(a(0)) for (i <- 1 to Nx2) { var prod_list = List(a(i)) for (j <- 0 to i - 1) { prod_list = (d - z(j))::prod_list } sum_list = (prod_list.product)::sum_list } sum_list.sum } }
Z:\>scala Scala0704.scala -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 -0.00000 0.00 0.00000 -0.00000 0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 0.00000 2.50 0.70964 0.70964 -0.00000 3.00 0.52500 0.52500 -0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 0.00000 4.50 4.68984 4.68984 0.00000
F#
module Fs0704 open System // データ点の数 - 1 let N = 6 let Nx2 = 13 // 元の関数 let f (x:double):double = x - Math.Pow(x,3.0) / (float (3 * 2)) + Math.Pow(x,5.0) / (float (5 * 4 * 3 * 2)) // 導関数 let fd (x:double):double = 1.0 - Math.Pow(x,2.0) / (float 2) + Math.Pow(x,4.0) / (float (4 * 3 * 2)) // Hermite (エルミート) 補間 let hermite(d:double) (z:double list) (a:double list) = let mutable sum_list = [a.[0]] for i in [1..Nx2] do let mutable prod_list = [a.[i]] for j in [0..i-1] do prod_list <- (d - z.[j])::prod_list sum_list <- (prod_list |> List.reduce(*))::sum_list sum_list |> List.sum // 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット let x = [0..N] |> List.map(fun i -> (float i) * 1.5 - 4.5) let y = x |> List.map(f) let yd = x |> List.map(fd) // 差分商の表を作る let z = [0..Nx2] |> List.map(fun i -> i / 2) |> List.map(fun j -> x.[j]) let d = Array2D.zeroCreate<double> (Nx2+1) (Nx2+1) for i in [0..Nx2] do d.[0,i] <- y.[i / 2] for i in [1..Nx2] do for j in [0..Nx2-i] do if (i = 1 && j % 2 = 0) then d.[i,j] <- yd.[j / 2] else d.[i,j] <- (d.[i-1,j+1] - d.[i-1,j]) / (z.[j+i] - z.[j]) // n階差分商 let a = [0..Nx2] |> List.map(fun i -> d.[i,0]) // 0.5刻みで 与えられていない値を補間 let d1 = [0..18] |> List.map(fun i -> (float i) * 0.5 - 4.5) let d2 = d1 |> List.map(f) let d3 = d1 |> List.map(fun d -> (hermite d z a)) (List.zip (List.zip d1 d2) d3) |> List.iter (fun ((d1, d2), d3) -> printfn "%5.2f\t%8.5f\t%8.5f\t%8.5f" d1 d2 d3 (d2 - d3)) exit 0
Z:\>fsi --nologo --quiet Fs0704.fs -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 0.00000 0.00000 0.50 0.47943 0.47943 0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 0.00000 4.50 4.68984 4.68984 0.00000
Clojure
(def N 7) (def Nx2 14) ; 元の関数 (defn f[x] (+ (- x (/ (Math/pow x 3.0) (* 3 2))) (/ (Math/pow x 5.0) (* 5 (* 4 (* 3 2)))))) ; 導関数 (defn fd[x] (+ (- 1.0 (/ (Math/pow x 2.0) 2)) (/ (Math/pow x 4.0) (* 4 (* 3 2))))) ; Hermite (エルミート) 補間 (defn hermite [d z a] (def sum_list (list (nth a 0))) (doseq [i (range 1 Nx2)] (def prod_list (list (nth a i))) (doseq [j (range 0 i)] (def prod_list (cons (- d (nth z j)) prod_list))) (def w (reduce * prod_list)) (def sum_list (cons w sum_list))) (reduce + sum_list)) ; 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット (def x (map #(- (* % 1.5) 4.5) (range 0 N))) (def y (map #(f %) x)) (def yd (map #(fd %) x)) ; 差分商の表を作る (def z (map #(nth x %) (map #(quot % 2) (range 0 Nx2)))) (def w (map #(nth y %) (map #(quot % 2) (range 0 Nx2)))) (def d (cons w nil)) (doseq [i (range 1 Nx2)] (def w (nth d 0)) (def t (list)) (doseq [j (range 0 (- Nx2 i))] (def t (cons (if (and (= i 1) (= (rem j 2) 0)) (nth yd (quot j 2)) (/ (- (nth w (+ j 1)) (nth w j)) (- (nth z (+ j i)) (nth z j))) ) t ) ) ) (def d (cons (reverse t) d)) ) (def d (reverse d)) ; n階差分商 (def a (map #(nth (nth d %) 0) (range 0 Nx2))) ; 0.5刻みで 与えられていない値を補間 (def d1 (map #(- (* % 0.5) 4.5) (range 0 19))) (def d2 (map #(f %) d1)) (def d3 (map #(hermite % z a) d1)) (doseq [d (map list d1 d2 d3)] (def d1 (nth d 0)) (def d2 (nth d 1)) (def d3 (nth d 2)) (println (format "%5.2f\t%8.5f\t%8.5f\t%8.5f" d1 d2 d3 (- d2 d3))))
Z:\>java -cp C:\ProgramFiles\clojure-1.5.1\clojure-1.5.1.jar clojure.main Clj0704.clj -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 -0.00000 0.00 0.00000 -0.00000 0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 0.00000 2.50 0.70964 0.70964 -0.00000 3.00 0.52500 0.52500 -0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 0.00000 4.50 4.68984 4.68984 0.00000
Haskell
import Text.Printf import Control.Monad -- データ点の数 - 1 n = 6 :: Int nx2 = 13 :: Int -- 元の関数 f::Double->Double f x = x - (x ^ 3) / (fromIntegral (3 * 2)) + (x ^ 5) / (fromIntegral (5 * 4 * 3 * 2)) -- 導関数 fd::Double->Double fd x = 1.0 - (x ^ 2) / (fromIntegral 2) + (x ^ 4) / (fromIntegral (4 * 3 * 2)) -- Hermite (エルミート) 補間 hermite::Double->[Double]->[Double]->Double hermite d z a = let sum_list = map(\i -> do let prod_list = map(\j -> do d - z!!j ) $ [0..(i-1)::Int] product $ a!!i : prod_list ) [1..nx2::Int] in sum $ a!!0 : sum_list -- 差分商の表を作る make_table::[Double]->[Double]->[Double]->[Double]->Int->[Double] make_table yd z d a i = let w = map(\j -> do if (i == 1 && (rem j 2) == 0) then yd!!(div j 2) else ((d!!(j+1) - d!!j) / (z!!(j+i) - z!!j)) ) $ [0..(nx2-i)::Int] t = w!!0:a in -- n階差分商 if i == nx2 then t else (make_table yd z w t (i + 1)) main = do -- 1.5刻みで -4.5~4.5 まで, 7点だけ値をセット let x = map(\i -> (fromIntegral i) * 1.5 - 4.5) [0..n] let y = map(\i -> f(i)) x let yd = map(\i -> fd(i)) x -- 差分商の表を作る let z = map(\i -> x!!(div i 2)) [0..nx2] let w = map(\i -> y!!(div i 2)) [0..nx2] let a = reverse (make_table yd z w [w!!0] 1) -- 0.5刻みで 与えられていない値を補間 let d1 = map(\i -> (fromIntegral i) * 0.5 - 4.5) [0..18] let d2 = map(\i -> (f i)) d1 let d3 = map(\i -> (hermite i z a)) d1 forM_ (zip (zip d1 d2) d3) $ \((d1, d2), d3) -> do printf "%5.2f\t%8.5f\t%8.5f\t%8.5f\n" d1 d2 d3 (d2 - d3)
Z:\>runghc Hs0704.hs -4.50 -4.68984 -4.68984 0.00000 -4.00 -1.86667 -1.86667 0.00000 -3.50 -0.73099 -0.73099 0.00000 -3.00 -0.52500 -0.52500 0.00000 -2.50 -0.70964 -0.70964 0.00000 -2.00 -0.93333 -0.93333 0.00000 -1.50 -1.00078 -1.00078 0.00000 -1.00 -0.84167 -0.84167 0.00000 -0.50 -0.47943 -0.47943 0.00000 0.00 0.00000 -0.00000 0.00000 0.50 0.47943 0.47943 -0.00000 1.00 0.84167 0.84167 0.00000 1.50 1.00078 1.00078 0.00000 2.00 0.93333 0.93333 -0.00000 2.50 0.70964 0.70964 0.00000 3.00 0.52500 0.52500 0.00000 3.50 0.73099 0.73099 0.00000 4.00 1.86667 1.86667 -0.00000 4.50 4.68984 4.68984 -0.00000