2021-2022年收藏的精品资料购房贷款问题.docx
实验二：购房贷款问题（1） 问题重述：初始贷款额为30万，借款期限不超过30年，对于不同的贷款期限，贷款利率有所不同。商业贷款和公积金年利率见下表（一年期为到期一次还本付息）贷款年限15年610年1120年2030年商业贷款0.05060.05470.05690.0592公积金贷款0.03720.04120.04440.0477根据上述贷款信息，制定一个完整的个人购房贷款本息月均还款额表，表中应包括借款年限，各自的月利率、月均还款额、总还款额和利息负担总额，还有采用商业贷款和采用公积金贷款的利息差价。（2） 问题分析：根据题意，在不同的时间阶段有不同的年利率，所以在不同的时间段要按不同的年利率来计算。（3） 算法设计：用switch 语句编程M文件daikun.m，再分别用year_num_1.m、year_num_2.m、year_num_3.m、year_num_4.m四个函数调用，根据不同时间来计算出该时间的所有要求量。（4） 程序：% daikun.mclc;clear;disp('贷款年数'),year_num=input('enter the number:')x=year_num;switch year_num case 1 year_num_1(1); case 2 year_num_1(2); case 3 year_num_1(3); case 4 year_num_1(4); case 5 year_num_1(5); case 6 year_num_2(6); case 7 year_num_2(7); case 8 year_num_2(8); case 9 year_num_2(9); case 10 year_num_2(10); case 11 year_num_3(11); case 12 year_num_3(12); case 13 year_num_3(13); case 14 year_num_3(14); case 15 year_num_3(15); case 16 year_num_3(16); case 17 year_num_3(17); case 18 year_num_3(18); case 19 year_num_3(19); case 20 year_num_3(20); case 21 year_num_4(21); case 22 year_num_4(22); case 23 year_num_4(23); case 24 year_num_4(24); case 25 year_num_4(25); case 26 year_num_4(26); case 27 year_num_4(27); case 28 year_num_4(28); case 29 year_num_4(29); case 30 year_num_4(30); otherwise disp('you enter the number is not between 1 and 30');end%year_num_1.mfunction y=year_num_1(x)disp('商业贷款方案1'), disp('月利率'), p1_1=0.0506/12 disp('月均还贷额'), p1_2=(30+30*0.0506*x)/(12*x) disp('总还贷额'), p1_3=30+30*0.0506*x disp('利息负担总额'), p1_4=30*0.0506*x disp('公积金贷款方案2'), disp('月利率'), p2_1=0.0372/12 disp('月均还贷额'), p2_2=(30+30*0.0372*x)/(12*x) disp('总还贷额'), p2_3=30+30*0.0372*x disp('利息负担总额'), p2_4=30*0.0372*x disp('商业贷款与公积金贷款的利息差价'), p1=p1_4-p2_4end%year_num_2.mfunction y=year_num_2(x)disp('商业贷款方案1'), disp('月利率'), p1_1=(0.0506*5+0.0547*(x-5)/(12*x) disp('月均还贷额'), p1_2=(30+30*0.0506*5+30*0.0547*(x-5)/(12*x) disp('总还贷额'), p1_3=30+30*0.0506*5+30*0.0547*(x-5) disp('利息负担总额'), p1_4=30*0.0506*5+30*0.0547*(x-5) disp('公积金贷款方案2'), disp('月利率'), p2_1=(0.0372*5+0.0412*(x-5)/(5*12+12*(x-5) disp('月均还贷额'), p2_2=(30+30*0.0372*5+30*0.0412*(x-5)/(12*x) disp('总还贷额'), p2_3=30+30*0.0372*5+30*0.0412*(x-5) disp('利息负担总额'), p2_4=30*0.0372*5+30*0.0412*(x-5) disp('商业贷款与公积金贷款的利息差价'), p1=p1_4-p2_4end%year_num_3.mfunction y=year_num_3(x)disp('商业贷款方案1'), disp('月利率'), p1_1=(0.0506*5+0.0547*5+0.0569*(x-10)/(12*x) disp('月均还贷额'), p1_2=(30+30*0.0506*5+30*0.0547*5+30*0.0569*(x-10)/(12*x) disp('总还贷额'), p1_3=(30+30*0.0506*5+30*0.0547*5+30*0.0569*(x-10) disp('利息负担总额'), p1_4=30*0.0506*5+30*0.0547*5+30*0.0569*(x-10) disp('公积金贷款方案2'), disp('月利率'), p2_1=(0.0372*5+0.0412*5+0.0444*(x-10)/(12*x) disp('月均还贷额'), p2_2=(30+30*0.0372*5+30*0.0412*5+30*0.0444*(x-10)/(12*x) disp('总还贷额'), p2_3=(30+30*0.0372*5+30*0.0412*5+30*0.0444*(x-10) disp('利息负担总额'), p2_4=30*0.0372*5+30*0.0412*5+30*0.0444*(x-10) disp('商业贷款与公积金贷款的利息差价'), p1=p1_4-p2_4end%year_num_4.mfunction y=year_num_4(x)disp('商业贷款方案1'), disp('月利率'), p1_1=(0.0506*5+0.0547*5+0.0569*10+0.0592*(x-20)/(12*x) disp('月均还贷额'), p1_2=(30+30*0.0506*5+30*0.0547*5+30*0.0569*10+30*0.0592*(x-20)/(12*x) disp('总还贷额'), p1_3=30+30*0.0506*5+30*0.0547*5+30*0.0569*10+30*0.0592*(x-20) disp('利息负担总额'), p1_4=30*0.0506*5+30*0.0547*5+30*0.0569*10+30*0.0592*(x-20) disp('公积金贷款方案2'), disp('月利率'), p2_1=(0.0372*5+0.0412*5+0.0444*10+0.0477*(x-20)/(12*x) disp('月均还贷额'), p2_2=(30+30*0.0372*5+30*0.0412*5+30*0.0444*10+30*0.0477*(x-20)/(12*x) disp('总还贷额'), p2_3=30+30*0.0372*5+30*0.0412*5+30*0.0444*10+30*0.0477*(x-20) disp('利息负担总额'), p2_4=30*0.0372*5+30*0.0412*5+30*0.0444*10+30*0.0477*(x-20) disp('商业贷款与公积金贷款的利息差价'), p1=p1_4-p2_4end（5） 计算结果：（A表示选择方案、B表示月利率、C表示月均还贷额、D表示总还贷额、K表示利息总负担、J表示利息差价、Y表示贷款年数）Y 1 2 3 4 5A商业公积金商业公积金商业公积金商业公积金商业公积金B0.00420.00310.00420.00310.00420.00310.00420.00310.00420.0031C2.62652.59301.37651.34300.95980.92630.75150.71800.62650.5930D31.51831.11633.03632.23234.55433.34836.07234.46437.59035.580K1.5181.11603.03602.23204.55403.34806.07204.46407.5905.580J 0.4020 0.8040 1.2060 1.6068 2.0100Y 6 7 8 9 10A商业公积金商业公积金商业公积金商业公积金商业公积金B0.00430.00320.00430.00320.00430.00320.00440.00320.00440.0033C0.54490.51130.48660.45300.44280.40920.40880.37520.38160.3480D39.23136.81640.87238.05242.51339.28844.15440.52445.79541.760K9.2316.81610.8728.05212.5139.288014.15410.52415.79511.760J 2.4150 2.8200 3.2250 3.6300 4.0350Y 11 12 13 14 15A商业公积金商业公积金商业公积金商业公积金商业公积金B0.00440.00330.00440.00330.00450.00340.00450.00340.00450.0034C0.35990.32650.34170.30850.32640.29330.31320.28030.30180.2690D47.50243.09249.20944.42450.91645.75652.62347.08854.33048.420K17.50213.09219.20914.42420.91615.75622.62317.08824.33018.420J 4.4100 4.7850 5.1600 5.53505.9100Y 16 7 18 19 20A商业公积金商业公积金商业公积金商业公积金商业公积金B0.00450.00340.00450.00340.00450.00350.00460.00350.00460.0035C0.29190.25910.28310.25040.27520.24270.26820.23570.26190.2295D56.03749.75257.74451.08459.45152.41661.15853.74862.86555.080K26.03719.75227.74421.08429.45122.41631.15823.74832.86525.080J 6.2850 6.6600 7.0350 7.4100 7.7850Y 21 22 23 24 25A商业公积金商业公积金商业公积金商业公积金商业公积金B0.00460.00350.00460.00350.00460.00350.00460.00360.00460.0036C0.25650.22420.25160.21950.24710.21510.24290.21110.23920.2075D64.64156.51166.41757.94268.19359.37369.96960.80471.74562.235K34.64126.51136.41727.94238.19329.37339.96930.80441.74532.235J 8.1300 8.4750 8.8200 9.1650 9.5100Y 26 27 28 29 30A商业公积金商业公积金商业公积金商业公积金商业公积金B0.00460.00360.00470.00360.00470.00360.00470.00360.00470.0036C0.23560.20410.23240.20090.22940.19800.22660.19350.22400.1928D73.52163.66675.29765.09777.07366.52878.84967.95980.62569.390K43.52133.66645.29735.09747.07336.52848.84937.95950.62539.390J 9.8550 10.2000 10.5450 10.8900 11.2350（6）结果分析： 根据题目给出的数据，利用本金和利息的计算公式，计算得出上面的各项数据经过四舍五入保留了小数位数的四位，结果已经是比较准确的了。（7）结论： 随着贷款时间越长，虽然商业贷款和公积金贷款的月利率和总的还贷额增大了，但是月均还贷额却减小了，这样就减小了人们每月的经济负担。还有随着贷款时间越长，商业贷款和公积金贷款的利息差价越大，所以较商业贷款，公积金贷款更加经济实惠。
