Error: File: t2_m1.m Line: 46 Column: 8 The input character is not valid in MATLAB statements or expressions.

x = (2:2:120);
c_1 = material_1(:, x);
vf_1 = mean(c_1,1);

v_m1 = (3*L*vf_1)/(4*w*h^2);

v_m1_sort = sort(v_m1);

i = (1:60);

p_f = (i-0.5)/60;

A_1 = log(v_m1_sort);
B_1 = log(log(1./(1-p_f)));

x1_1 = 4.98;
x2_1 = 5.206;
y1_1 = -1.285;
y2_1 = -0.1102;

m_1 = (y2_1-y1_1)/(x2_1-x1_1)   

eq_1 = polyfit(A_1,B_1,1);
bb_1 = eq_1(2);

v0_1 = exp(-bb_1/m_1);

G_1 = log(1-0.1);
H_1 = real(log(G_1));
I_1 = (H_1/m_1);
vv_1 = exp(I_1);
stress_1 = vv_1*v0_1; 

Answer 1

[dpb]

Unrecognized function or variable 'material_1'. 
>> material_1=rand(10,120);
>> x = (2:2:120);
c_1 = material_1(:, x);
vf_1 = mean(c_1,1);

v_m1 = (3*L*vf_1)/(4*w*h^2);

v_m1_sort = sort(v_m1);

i = (1:60);

p_f = (i-0.5)/60;

A_1 = log(v_m1_sort);
B_1 = log(log(1./(1-p_f)));

x1_1 = 4.98;
x2_1 = 5.206;
y1_1 = -1.285;
y2_1 = -0.1102;

m_1 = (y2_1-y1_1)/(x2_1-x1_1)   

eq_1 = polyfit(A_1,B_1,1);
bb_1 = eq_1(2);

v0_1 = exp(-bb_1/m_1);

G_1 = log(1-0.1);
H_1 = real(log(G_1));
I_1 = (H_1/m_1);
vv_1 = exp(I_1);
stress_1 = vv_1*v0_1; 
Unrecognized function or variable 'L'. 
>> L=1;
>> x = (2:2:120);
c_1 = material_1(:, x);
vf_1 = mean(c_1,1);

v_m1 = (3*L*vf_1)/(4*w*h^2);

v_m1_sort = sort(v_m1);

i = (1:60);

p_f = (i-0.5)/60;

A_1 = log(v_m1_sort);
B_1 = log(log(1./(1-p_f)));

x1_1 = 4.98;
x2_1 = 5.206;
y1_1 = -1.285;
y2_1 = -0.1102;

m_1 = (y2_1-y1_1)/(x2_1-x1_1)   

eq_1 = polyfit(A_1,B_1,1);
bb_1 = eq_1(2);

v0_1 = exp(-bb_1/m_1);

G_1 = log(1-0.1);
H_1 = real(log(G_1));
I_1 = (H_1/m_1);
vv_1 = exp(I_1);
stress_1 = vv_1*v0_1; 
Unrecognized function or variable 'w'. 
>> w=1;h=1;
>> x = (2:2:120);
c_1 = material_1(:, x);
vf_1 = mean(c_1,1);

v_m1 = (3*L*vf_1)/(4*w*h^2);

v_m1_sort = sort(v_m1);

i = (1:60);

p_f = (i-0.5)/60;

A_1 = log(v_m1_sort);
B_1 = log(log(1./(1-p_f)));

x1_1 = 4.98;
x2_1 = 5.206;
y1_1 = -1.285;
y2_1 = -0.1102;

m_1 = (y2_1-y1_1)/(x2_1-x1_1)   

eq_1 = polyfit(A_1,B_1,1);
bb_1 = eq_1(2);

v0_1 = exp(-bb_1/m_1);

G_1 = log(1-0.1);
H_1 = real(log(G_1));
I_1 = (H_1/m_1);
vv_1 = exp(I_1);
stress_1 = vv_1*v0_1; 
m_1 =
    5.1982
>> 

No problem with what was pasted other than not all variables were defined...