we took deez from gingerman thank you :D

expon.m

@@ -0,0 +1,15 @@
+% exponential model a * exp(b * x) 
+% y = a + b x
+clear;clc;close all;
+x = input("enter values of x:\n");
+y = input("enter values of y:\n");
+Y = log(y);
+n = length(x);
+coeff = [n sum(x);sum(x) sum(x.^2)];
+f_terms = [sum(Y);sum(x.*Y)];
+results = inv(coeff) * f_terms;
+A = results(1);
+a = exp(A);
+b = results(2);
+f = a * exp(b*x);
+plot(x, y,'',x, f);

growth_rate.m

@@ -0,0 +1,19 @@
+% growth rate model (a * x) / (b + x)
+% y = a + b x
+clear;clc;close all;
+x = input("enter values of x:\n");
+y = input("enter values of y:\n");
+%x = [1,2,3,4,5,6]
+%y = [2,4,6,8,10,12]
+Y = y.^-1;
+X = x.^-1;
+n = length(x);
+coeff = [n sum(X);sum(X) sum(X.^2)];
+f_terms = [sum(Y);sum(X.*Y)];
+results = inv(coeff) * f_terms;
+A = results(1);
+B = results(2);
+a = 1 / A;
+b = B * a;
+f = (a.*x)./(b+x);
+plot(x, y,'',x, f);

linear_regression.m

@@ -0,0 +1,15 @@
+% linear regression
+% y = a + b x
+clear;clc;close all;
+%x = input("enter values of x:\n");
+%y = input("enter values of y:\n");
+x = [1 2 3 4 5];
+y = [2 3 4 5 6];
+n = length(x);
+coeff = [sum(x) n;sum(x) sum(x.^2)];
+f_terms = [sum(y);sum(x.*y)];
+results = inv(coeff) * f_terms;
+a = results(1);
+b = results(2);
+f = a + b * x;
+plot(x, y,'', x, f);

poly.m

@@ -0,0 +1,18 @@
+% poly a + b * x + c * x^2
+clear;clc;close all;
+x = input("enter values of x:\n");
+y = input("enter values of y:\n");
+n = length(x);
+coeff = [n sum(x) sum(x.^2)
+        sum(x) sum(x.^2) sum(x.^3)
+        sum(x.^2) sum(x.^3) sum(x.^4)];
+f_terms = [sum(y)
+           sum(x.*y)
+           sum((x.^2).*y)];
+results = inv(coeff) * f_terms;
+a = results(1);
+b = results(2);
+c = results(3);
+
+f = a + b .* x + c .* x.^2;
+plot(x, y, '', x, f);

power_model.m

@@ -0,0 +1,16 @@
+% power model a * x ^ b
+% y = a + b x
+clear;clc;close all;
+x = input("enter values of x:\n");
+y = input("enter values of y:\n");
+Y = log(y);
+X = log(x);
+n = length(x);
+coeff = [n sum(X);sum(X) sum(X.^2)];
+f_terms = [sum(Y);sum(X.*Y)];
+results = inv(coeff) * f_terms;
+A = results(1);
+a = exp(A);
+b = results(2);
+f = a * x.^b;
+plot(x, y,'', x, f);