# How to change exponentiation

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Anton Anton on 20 Nov 2020
Commented: Anton Anton on 20 Nov 2020
Hello,
I want to change exponentiation from ^-5 to ^-6 and too format but will that 2. The command window is dense how can to do that line spacing.
Example the strain tensor is:
I need it accuracy to be like that:
Thanks for the helpers :)
My code:
clc;
clear;
sigma=input('Insert normal stresses[Mpa] and shear stresse[Mpa] of the cauchy stress tensor:');
sigma_xx=sigma(1,1);
tau_xy=sigma(1,2);
tau_xz=sigma(1,3);
tau_yx=sigma(2,1);
sigma_yy=sigma(2,2);
tau_yz=sigma(2,3);
tau_zx=sigma(3,1);
tau_zy=sigma(3,2);
sigma_zz=sigma(3,3);
disp('The matrix is'); disp(sigma);
Metal = input('Insert type of a metal material:','s');
switch Metal
case 'AISI1020'
S_y = 427;
G = 80000;
v = 0.29;
E = 207000;
case 'Alloy6061-T6'
S_y = 276;
G = 26000;
v = 0.33;
E = 69000;
case 'SAE4340'
S_y = 910;
G = 83000;
v = 0.29;
E = 214000;
end
epsilon_x=(1/E)*((sigma_xx)-v*((sigma_yy)+(sigma_zz))) ;
epsilon_y=(1/E)*((sigma_yy)-v*((sigma_zz)+(sigma_xx))) ;
epsilon_z=(1/E)*((sigma_zz)-v*((sigma_xx)+(sigma_yy))) ;
gamma_xy=(tau_xy)/(2*G) ;
gamma_xz=(tau_xz)/(2*G) ;
gamma_yz=(tau_yz)/(2*G) ;
gamma_yx=gamma_xy;
gamma_zx=gamma_xz;
gamma_zy=gamma_yz;
epsilon=zeros(3,3);
epsilon(1,1)=epsilon_x;
epsilon(1,2)=gamma_xy;
epsilon(1,3)=gamma_xz;
epsilon(2,1)=gamma_yx;
epsilon(2,2)=epsilon_y;
epsilon(2,3)=gamma_yz;
epsilon(3,1)=gamma_zx;
epsilon(3,2)=gamma_zy;
epsilon(3,3)=epsilon_z;
disp('The strain tensor is')
fprintf('%g %g %g\n',epsilon)

Star Strider on 20 Nov 2020
I wrote a littlle utility function for my own use a while back to do this.
Adapt it to do what you want:
expstr = @(x,n) [x(:).*10.^(-n*floor(log10(abs(x(:)))/abs(n))) n*floor(log10(abs(x(:)))/abs(n))];
a=-0.07639297;
Result1 = sprintf('%.7fE%+04d', expstr(a,2))
Result2 = sprintf('%.7fE%+04d', expstr(a,6))
Result3 = sprintf('%.7fE%+04d', expstr(a,-4))
producing:
Result1 =
'-7.6392970E-002'
Result2 =
'-76392.9700000E-006'
Result3 =
'-0.0000076E+004'
.

Steven Lord on 20 Nov 2020
Change the display format.
format % default which is "format short"
e = [5.45894e-6, -1.875e-5, 6.25e-6; ...
-1.875e-5, 1.79227e-5, 3.125e-5; ...
6.25e-6, 3.125e-5, -1.32367e-5];
disp(e)
1.0e-04 * 0.0546 -0.1875 0.0625 -0.1875 0.1792 0.3125 0.0625 0.3125 -0.1324
format long
disp(e)
1.0e-04 * 0.054589400000000 -0.187500000000000 0.062500000000000 -0.187500000000000 0.179227000000000 0.312500000000000 0.062500000000000 0.312500000000000 -0.132367000000000
format shorteng
disp(e)
5.4589e-006 -18.7500e-006 6.2500e-006 -18.7500e-006 17.9227e-006 31.2500e-006 6.2500e-006 31.2500e-006 -13.2367e-006

#### 1 Comment

Anton Anton on 20 Nov 2020
Thank you! You helped me too :)