24小时热门版块排行榜    

查看: 4429  |  回复: 7

雨人007

银虫 (小有名气)

[求助] MATLAB 中V4插值原理和计算步骤,急求!

MATLAB 中V4插值原理和计算步骤,求大神详解!
回复此楼

» 猜你喜欢

» 本主题相关价值贴推荐,对您同样有帮助:

想做的事情挡不住!
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

Kevlar_J

铜虫 (正式写手)

看帮助文件有没有?

[ 发自小木虫客户端 ]
振叶以寻根,观澜而溯源!www.source-grid.com
2楼2014-12-24 00:39:11
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

雨人007

银虫 (小有名气)

引用回帖:
2楼: Originally posted by Kevlar_J at 2014-12-24 00:39:11
看帮助文件有没有?

查了好多,有的也只是一概而过
想做的事情挡不住!
3楼2014-12-24 16:38:22
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

Kevlar_J

铜虫 (正式写手)

引用回帖:
3楼: Originally posted by 雨人007 at 2014-12-24 16:38:22
查了好多,有的也只是一概而过...

我觉得v4是他们自己算法,应该不会全部公开

[ 发自小木虫客户端 ]
振叶以寻根,观澜而溯源!www.source-grid.com
4楼2014-12-24 23:21:26
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

雨人007

银虫 (小有名气)

引用回帖:
4楼: Originally posted by Kevlar_J at 2014-12-24 23:21:26
我觉得v4是他们自己算法,应该不会全部公开
...

从MATLAB中找出的源程序,直接不懂!
>>type griddata
function [xi,yi,zi] = gdatav4(x,y,z,xi,yi)
%GDATAV4 MATLAB 4 GRIDDATA interpolation

%   Reference:  David T. Sandwell, Biharmonic spline
%   interpolation of GEOS-3 and SEASAT altimeter
%   data, Geophysical Research Letters, 2, 139-142,
%   1987.  Describes interpolation using value or
%   gradient of value in any dimension.

xy = x( + y(*sqrt(-1);

% Determine distances between points
d = xy(:,ones(1,length(xy)));
d = abs(d - d.');
n = size(d,1);
% Replace zeros along diagonal with ones (so these don't show up in the
% find below or in the Green's function calculation).
d(1:n+1:numel(d)) = ones(1,n);

non = find(d == 0, 1);
if ~isempty(non),
  % If we've made it to here, then some points aren't distinct.  Remove
  % the non-distinct points by averaging.
  [r,c] = find(d == 0);
  k = find(r < c);
  r = r(k); c = c(k); % Extract unique (row,col) pairs
  v = (z(r) + z(c))/2; % Average non-distinct pairs
  
  rep = find(diff(c)==0);
  if ~isempty(rep), % More than two points need to be averaged.
    runs = find(diff(diff(c)==0)==1)+1;
    for i=1:length(runs),
      k = (c==c(runs(i))); % All the points in a run
      v(runs(i)) = mean(z([r(k);c(runs(i))])); % Average (again)
    end
  end
  z(r) = v;
  if ~isempty(rep),
    z(r(runs)) = v(runs); % Make sure average is in the dataset
  end

  % Now remove the extra points.
  z(c) = [];
  xy(c, = [];
  xy(:,c) = [];
  d(c, = [];
  d(:,c) = [];
  
  % Determine the non distinct points
  ndp = sort([r;c]);
  ndp(ndp(1:length(ndp)-1)==ndp(2:length(ndp))) = [];

  warning('MATLAB:griddata:NonDistinctPoints',['Averaged %d non-distinct ' ...
            'points.\n         Indices are: %s.'],length(ndp),num2str(ndp'))
end

% Determine weights for interpolation
g = (d.^2) .* (log(d)-1);   % Green's function.
% Fixup value of Green's function along diagonal
g(1:size(d,1)+1:numel(d)) = zeros(size(d,1),1);
weights = g \ z(;

[m,n] = size(xi);
zi = zeros(size(xi));
jay = sqrt(-1);
xy = xy.';

% Evaluate at requested points (xi,yi).  Loop to save memory.
for i=1:m
  for j=1:n
    d = abs(xi(i,j)+jay*yi(i,j) - xy);
    mask = find(d == 0);
    if ~isempty(mask), d(mask) = ones(length(mask),1); end
    g = (d.^2) .* (log(d)-1);   % Green's function.
    % Value of Green's function at zero
    if ~isempty(mask), g(mask) = zeros(length(mask),1); end
    zi(i,j) = g * weights;
  end
end

if nargout<=1,
  xi = zi;
end
想做的事情挡不住!
5楼2014-12-25 10:22:14
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

Kevlar_J

铜虫 (正式写手)

引用回帖:
5楼: Originally posted by 雨人007 at 2014-12-25 10:22:14
从MATLAB中找出的源程序,直接不懂!
>>type griddata
function  = gdatav4(x,y,z,xi,yi)
%GDATAV4 MATLAB 4 GRIDDATA interpolation

%   Reference:  David T. Sandwell, Biharmonic spline
%   int ...

这说的我也不懂,我觉得一句句翻译成数学语言,应该可以理解的,别急,慢慢看

[ 发自小木虫客户端 ]
振叶以寻根,观澜而溯源!www.source-grid.com
6楼2014-12-25 12:11:43
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

Kevlar_J

铜虫 (正式写手)

引用回帖:
5楼: Originally posted by 雨人007 at 2014-12-25 10:22:14
从MATLAB中找出的源程序,直接不懂!
>>type griddata
function  = gdatav4(x,y,z,xi,yi)
%GDATAV4 MATLAB 4 GRIDDATA interpolation

%   Reference:  David T. Sandwell, Biharmonic spline
%   int ...

有什么不懂到matlab爱好者论坛问问,哪里大神多

[ 发自小木虫客户端 ]
振叶以寻根,观澜而溯源!www.source-grid.com
7楼2014-12-25 12:12:29
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

雨人007

银虫 (小有名气)

引用回帖:
7楼: Originally posted by Kevlar_J at 2014-12-25 12:12:29
有什么不懂到matlab爱好者论坛问问,哪里大神多
...

多谢啊!
想做的事情挡不住!
8楼2014-12-26 10:02:01
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
相关版块跳转 我要订阅楼主 雨人007 的主题更新
最具人气热帖推荐 [查看全部] 作者 回/看 最后发表
[考博] 澳大利亚 Murdoch University 全奖博士招生(3个名额)地质化工冶金领域 +38 AI8RaGaPaSCR 2026-08-07 40/2000 2026-08-13 23:45 by 9kfQ6ZJVaWOC
[基金申请] 咱们一起用铁证分析2026国家社科基金中标与否 +3 启萌科技 2026-08-12 11/550 2026-08-13 22:57 by 启萌科技
[基金申请] 欢迎发来filecode的Mz6后的代码验证其规律 +10 医学老男孩 2026-08-13 28/1400 2026-08-13 22:44 by 医学老男孩
[基金申请] 小木虫上这么多卖论文的,真有人买论文么?感觉没必要啊 +9 Tide man 2026-08-10 10/500 2026-08-13 20:33 by 温淼淼淼
[硕博家园] 一作与独作在应聘高校教师时区别大吗 +3 mbygzh 2026-08-08 4/200 2026-08-13 19:31 by 龙-樱
[基金申请] 静等基金结果 +8 gjjjzhong 2026-08-10 21/1050 2026-08-13 17:56 by 且听虎啸
[基金申请] 有时候,自然基金真的不能太认真 (我的申报经验) +4 majunge000 2026-08-11 6/300 2026-08-13 16:50 by 四季常青藤
[基金申请] 重要来源:本周末出结果 +10 瞬息宇宙 2026-08-12 10/500 2026-08-13 15:46 by likettle
[基金申请] 不应该看fileCode +7 且听虎啸 2026-08-12 9/450 2026-08-13 14:27 by flydreamws
[基金申请] 应该是93bebmhtak前后十一个字符比较关键 +22 Lanmanbaby 2026-08-09 36/1800 2026-08-12 22:50 by sdfapple719
[论文投稿] 职称评审,求友友推荐见刊最快的期刊 +4 工厂打螺丝 2026-08-08 4/200 2026-08-12 09:18 by hansi2025
[基金申请] 综述论文作为代表作会不会影响评审专家的印象分? +11 yufeiwaner 2026-08-09 13/650 2026-08-12 08:17 by yufeiwaner
[基金申请] 是这周出结果还是下周出结果? +3 yuleib84 2026-08-11 3/150 2026-08-11 21:53 by jnhyjjm
[硕博家园] 读博的好处 +3 lnee 2026-08-11 3/150 2026-08-11 18:10 by 希望我好好的
[基金申请] 什么时候出结果,有咨询渠道??? +3 Tide man 2026-08-11 3/150 2026-08-11 17:54 by kudofaye
[基金申请] 国自然结果 +4 Vierhys 2026-08-10 8/400 2026-08-10 15:06 by Vierhys
[基金申请] 面上项目filecode邪修 +5 西山十月 2026-08-09 7/350 2026-08-10 07:32 by 仁砚薪传
[基金申请] fileCode有新解读? +10 Tide man 2026-08-08 18/900 2026-08-09 12:55 by 仁砚薪传
[基金申请] 关于filecode,很负责任的告诉大家 +6 爱看书的可乐 2026-08-08 7/350 2026-08-08 22:13 by a_niu
[基金申请] 关于filecode +4 布布和一二 2026-08-07 7/350 2026-08-07 22:55 by zhanghaozhu
信息提示
请填处理意见