jalachniet

% function file 'dblint.m'
%   evaluates dblquad(f, x1, x2, y1, y2)
%   where f is an anonymous function of x and y
%   y1 and y2 are anonymous functions of x
%   x1 and x2 are real numbers

function val = dblint(f, x1, x2, y1, y2)
   f2 = @(x, u) f(x, y1(x) + u.*(y2(x) - y1(x))) .* (y2(x) - y1(x));
   val = dblquad(f2, x1, x2, 0, 1);
end

jalachniet

% function file 'linReg.m' runs a standard linear regression analysis
%   syntax: [P r] = linReg(x, y)
%   displays regression equation and correlation data, draws scatter plot
%   optional return values P: regression equation, r: correlation coefficient

function [P r] = linReg(x, y)
  % calculate regression and correlation
  P  = polyfit(x, y, 1);
  r = corr(x, y);
  

jalachniet

% script file 'cave_spline.m'
%   generates spline curves for walls, ceiling, and floor
%   plots plan and profile views of survey line and spline model
%   requires 10x1 station coordinate vectors x, y, and z and 10x4 lrud data matrix

% extract left, right, up, down from lrud data matrix
load csurvey_data.txt
L = lrud(:, 1);
R = lrud(:, 2);
U = lrud(:, 3);

jalachniet

% Created by Octave 5.1.0, Wed Feb 19 09:02:40 2020 GMT <unknown@jlachniet-LT>
% name: data
% type: matrix
% rows: 9
% columns: 3
 30.05 248.5 -15.5
 10.3 237.5 -25.5
 3.2 245 11
 17 269 -5
 10 271 -10

jalachniet

function mesh2stl(filename, X, Y, Z, delta)
%MESH2STL writes an .stl (STereoLithography) file from meshgrid variables
%  mesh2stl('filename', X, Y, Z)
%     produces a triangulated mesh from meshgrid variables X, Y, Z
%     and writes output to 'filename' in stl format 
%  --X, Y, Z must be two dimensional arrays of the same size
%  --optional: if delta is provided, produce a solid block from the graph
%              of surface z = f(x, y)
%              where 'delta' gives minimum thickness between base of block
%              and graph of surface