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Matlab

One-dimensional linear interpolation

One-dimensional interpolation command

%x:原始数据（自变量）n维向量
%v:原始数据（函数值）n维向量
%xq:插值（自变量）可以使一个点，也可以是向量
%vq:插值结果（函数值）
vq = interp1(x,v,xq)
vq = intterp1(x,v,xq,method)

method

The 2014a version of matlab currently has these methods:

Example 1-Interpolation method:

The implementation script code is as follows:

production = [75.995 ... .... ..] %此处省了，实则是产量的值
years = 1900:10:2010;  %设置年份区间
x = 1900:2010;
p_res = interp1(years,production,x,'spline')
plot(years,production,'o',x,p_res)

Run to get a continuous line.

Example 2-Interpolation method:

The implementation script code is as follows:

x = 0:2:24;
y = [....]   %温度的值
% 注意：x和y的维度要一样，形成一一对应关系
x1 = 0:1/3600:24   %单位化成秒，增量为1s

strmethod={
    
    'nearest',...}  %方法
strlb={
    
    '{a}method=nearest',...}  %对应上方的方法

for i=1:6
	y1 = interp1(x,y,x1,strmethod{
    
    i});
	subplot(3,2,i)    %切割出3*2张图
	plot(x,y,'ro',x1,y1,'b''linewith',1.5)
	xlabel(strlb)
end

The effect is as follows: