diff options
Diffstat (limited to '964/CH22/EX22.4/22_4.sce')
| -rwxr-xr-x | 964/CH22/EX22.4/22_4.sce | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/964/CH22/EX22.4/22_4.sce b/964/CH22/EX22.4/22_4.sce new file mode 100755 index 000000000..6a9e062e5 --- /dev/null +++ b/964/CH22/EX22.4/22_4.sce @@ -0,0 +1,18 @@ +//clc()
+//f(x) = 0.2 + 25*x - 200*x^2 + 675*x^3 - 900*x^4 + 400*x^5
+// for using three point gauss legendre formulae, the intervals have to be changed to -1 and 1
+//therefore, x = 0.4 + 0.4 * xd
+//thus the integral is transferred to
+//(0.2 + 25*(0.4+0.4*x) - 200*(0.4 + 0.4*x)^2 + 675*(0.4 + 0.4*x)^3 - 900*(0.4 + 0.4*x)^4 + 400*(0.4 + 0.4*x)^5)*0.4
+//for three point gauss legendre formulae
+x1 = -0.7745967;
+x2 = 0;
+x3 = 0.7745967;
+c0 = 0.5555556;
+c1 = 0.8888889;
+c2 = 0.5555556;
+I1 = (0.2 + 25*(0.4+0.4*x1) - 200*(0.4 + 0.4*x1)^2 + 675*(0.4 + 0.4*x1)^3 - 900*(0.4 + 0.4*x1)^4 + 400*(0.4 + 0.4*x1)^5)*0.4;
+I2 = (0.2 + 25*(0.4+0.4*x2) - 200*(0.4 + 0.4*x2)^2 + 675*(0.4 + 0.4*x2)^3 - 900*(0.4 + 0.4*x2)^4 + 400*(0.4 + 0.4*x2)^5)*0.4;
+I3 = (0.2 + 25*(0.4+0.4*x3) - 200*(0.4 + 0.4*x3)^2 + 675*(0.4 + 0.4*x3)^3 - 900*(0.4 + 0.4*x3)^4 + 400*(0.4 + 0.4*x3)^5)*0.4;
+I = c0 * I1 + c1 * I2 + c2 * I3;
+disp(I,"integral obtained using three point gauss legendre formulae = ")
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